Defining an Anti-Dynasty: The Worst NFL Teams Ever
They finally did it. After wallowing in misery for nearly two decades, the Cleveland Browns had a taste of postseason success in 2020. The longest playoff drought of the 21st century? Over and done with. Thirteen seasons at the bottom of their division, with three at the bottom of the league as a whole? Firmly in the rearview mirror. 0-16? Done! Trent Richardson, Johnny Manziel, Corey Coleman, Justin Gilbert? Forgiven! A new era of football is born in Cleveland. Kevin Stefanski, Baker Mayfield, Myles Garrett and the rest will drive the Browns forward into an era of prosperity not seen in Cleveland since the 1950s … right?
On the other hand, the Jacksonville Jaguars thought their troubles were over when the #Sacksonville squad rolled their way to the AFC Championship Game back in 2017. Their subsequent 12-36 record is a reminder that one year's worth of success is not always enough to fully free a team from the swampland of putrid football, and that sometimes the light at the end of the tunnel is indeed the oncoming train. Saddled with the top pick in the 2021 draft, the Jaguars are now counting on Trevor Lawrence to lead them back to respectability, and top draft picks always end up working out just fine … right?
Last offseason, we spent the month of May counting down the top dynasties the NFL has ever seen, from George Halas' 1920s Bears to Patrick Mahomes' 2010s Chiefs. This year, by popular demand, we're flipping the script. We're digging deep into the bowels of NFL history to try to find the worst of the worst; the teams that did the most to set football back through combinations of injuries, incompetence, and ineptitude. We're here to celebrate the teams that showed up week in and week out only to lose by four scores in front of nearly empty stands. We're looking at the owners and general managers who went out of their way to make the wrong personnel decisions, torpedoing their teams for years. We're wading through the worst trades, the worst performances, the worst drafts, the worst starters, the worst everything. In short, we're on the hunt to find the Anti-Dynasty.
This seems like a perfect year to go hunting, too. Both the Browns and Buccaneers' 2020 playoff runs ended droughts that had lasted for more than a decade; a very strong point on any team's Anti-Dynasty resume. It's quite possible that we saw an epic changing-of-the-guard moment when it comes to terrible football last year, so it's an ideal time to take stock at the worst of the worst to date.
We'll be honest—this is a very silly idea. Most scholarly attempts at ranking players and teams have dealt with classifying the very best the league has had to offer. If they bother at all to try to look at poor performance, they'll usually just take win-loss record over a given window and call it a day. But this is Football Outsiders, home of the Keep Choppin' Wood Team and the Loser League. If there's anyone out there qualified to be the keeper of the Wooden Spoon, it's us.
Trying to place the worst teams in NFL history into one ranking brings us challenges that we didn't encounter when looking at the cream of the crop. There's a general consensus on what being a good team requires; we count championships and division titles and deep playoff runs, and whoever has the most wins. But which is worse, a team going three or four years with three or four wins a season, being penciled in as an easy win around the league? Or a team that spends a decade and a half mired in 5- to 7-win hell, never bottoming out but never really being in contention? The worst of the worst will combine the best of both, of course, and there are plenty of teams with a rotten two- or three-year core surrounded by a shell of mediocrity, but that's a tough nut to crack. Both the Jeff Fisher Rams and the post-Jim Harbaugh 49ers deserve their chances to be heard, and fans of both teams deserve a place to vent and commiserate. Our final rankings will have short-lived nightmares mixed in with long-term malaise, each team being terrible in its own beautiful, unique way.
To try to impose some order to unto chaos, we're returning to the idea of each season earning a certain number of (anti)-dynasty points. Those three- and four-win seasons are going to be worth more than those five- and seven-win years, for sure, but every little bit of losing helps. We're basically just counting how far under .500 a team finishes, with the twist that winning seasons exponentially erase a team's progress towards terribleness. The franchises that piled up year after year of disappointing seasons will rise to the top and get their due.
Ah, but we wouldn't be Football Outsiders if we just counted wins and losses and called it a day—we need to separate the chaff from the wheat. Anti-dynasty points are a counting stat; they measure the quantity of terribleness a franchise puts up. That's all very good and very important, but not all poor seasons are made equal. The 49ers and Giants both went 6-10 in 2020, but San Francisco's 5.4% DVOA dwarfs New York's -13.8%; San Francisco was a significantly better team, and our rankings need to take that into account. With nearly 40 years of DVOA behind us, we can differentiate between the 2008 0-16 Lions and 2017 0-16 Browns, as well as acknowledge the teams that were worse than both despite better results on the field. You are what your record says you are, of course, but some records speak more eloquently than others.
What we are unveiling this month, then, is really twofold. In this article, we're going to be listing every team that has ever ranked up at least 30 of our anti-dynasty points—all the bottom-feeders, schedule-fillers, and wet paper bags that have ever disgraced a gridiron. We'll show which teams had the most quantity of terribleness—the top draft picks, the bottoms of their divisions and conferences, and the blowout losses to justify the lot. This is the list of the biggest anti-dynasties the sport has ever seen.
And then, in a series of articles that will be released over the course of this month, we'll look at each one of those dreadful teams in turn, and blend in DVOA (or estimated DVOA for teams before 1983) to produce a record that factors in a team's lack of quality beyond simple wins and losses. Compilers will make way for short-term nightmares, and we'll eventually crown the worst run any NFL football team has ever had. That will be a list of the worst anti-dynasties the sport has ever seen.
Best anti-dynasties? Most anti-dynasty-esque? Least likely to succeed? Well, we'll work on the nomenclature as we're going along.
These links will gradually update as we rank 58 different anti-dynasties:
- Defining an Anti-Dynasty (June 2)
- Part I: No. 51-58 (June 2)
- Part II: No. 41-50 (June 8)
- Part III: No. 31-40 (June 10)
- Part IV: No. 21-30 (June 15)
- Part V: No. 11-20 (June 17)
- Part VI: No. 1-10 (June 22)
For the Dynasty Rankings, we had a complicated system where teams earned differing numbers of points based on regular- and postseason success. A 10-6 team that won a Super Bowl was seen as more dynastic than a 13-3 team that lost in the divisional round, but less dynastic than a 12-4 team that won the Super Bowl; it was a delicate balance of regular and postseason success.
That's not necessary for anti-dynasties. Bad teams generally do not make the postseason very often! We can solely focus on regular season success, or lack thereof.
There was still some consideration given to running the dynasty point system in reverse—teams that finish dead last in the league getting a set number of points, and then additional points for teams that finish in the bottom third or quartile and so forth. But finishing at the bottom of the standings is qualitatively different than finishing at the top. Had the 2020 Bears made a shocking playoff run and won the Super Bowl, they would consider their season a massive success despite middling results in the regular season. That's not true at the bottom. Fans of the 2020 Jets don't feel better about their team just because the Jaguars finished with one fewer win; if anything, that makes them feel worse about the year because they stunk and didn't even earn the top draft pick for their troubles. We'll take league, conference, and divisional standing into account later, but not for the anti-dynasty points themselves.
So, for teams in the 16-game era (1978-2020, may it rest in peace), this is how anti-dynasty points work:
If you had a losing record, your anti-dynasty points are simply your total losses minus your total wins. If you go 7-9, that's worth 2 anti-dynasty points. If you go 4-12, that's worth 8 anti-dynasty points. If you go 5-6-5 because your team is really bad at overtime, that's worth 1 anti-dynasty point—seasons with ties are the only way for teams from this era to earn an odd number of anti-dynasty points.
If you had a winning record, you get negative anti-dynasty points for your difference between wins and losses—squared. A winning season cures a lot of old wounds, so you can lose dynasty points a lot faster than you can pick them up. A 9-7 season is only worth -4 anti-dynasty points, but it starts escalating very quickly—10-6 will lose you 16, 11-5 will cost you 36, and 12-4 will wipe out 64 anti-dynasty points in one go. Teams can't go into negative numbers, but going to zero is one of two ways to definitively end an anti-dynasty. Only 15 teams, at the peak of their worst football, could survive a 12-4 season without being set back down to zero; those decade-long disasters see even very good seasons be looked at with a skeptical eye. Every single run would get wiped out by a 14-2 season.
That's all well and good, but it would give an unfair advantage to modern teams—they play more games, so theoretically can rack up more points. Should the 1976 Buccaneers be penalized for "only" going 0-14? Of course not. So, teams from the 10-, 12-, and 14- game eras get their seasons prorated out to 16 full games. They also get rounded just to make the numbers a little neater; a 4-10 season is worth 7 anti-dynasty points, not 6.9, and an 8-4 season is worth -25 points, not -28.4.
That, too, is all well and good, but now we've given an unfair advantage to ancient teams. Saying the 1925 0-9 Columbus Tigers should get equal credit to the 2017 0-16 Cleveland Browns is a stretch. Saying the 1921 0-1 Tonawanda Kardex deserves the same credit is ludicrous on its face. So for teams who played less than 10 games in a season, anti-dynasty points revert to straight number of games under .500. An 0-5 team gets 5 points, an 0-7 team gets 7 points, and so forth. This prevents the top of the list from being just slammed with fly-by-night travel teams from the 1920s—sure, they were really bad, but going 0-4 for five straight years while beating up local sandlot teams shouldn't be in the same category of a modern professional team forgetting how to snap the ball. And, while not relevant for anti-dynasty points, the DVOAs for these teams also get cut, to prevent small sample sizes from dominating the quality rankings; if you only played four games, your DVOA counts at 40% for ranking purposes.
This actually groups 1982 in with some of those teams from strange 1920s seasons; the strike limited teams to just nine games. It turns out, however, that giving full credit to 1982 would have … no effect whatsoever on which teams did or did not qualify for the table. 1982 happened to be the last winning season for years for the Tampa Bay Buccaneers, Atlanta Falcons, and San Diego Chargers, and the five active anti-dynasties from that era (the Saints, Giants, Colts, Oilers, and Bills) all had losing records anyway. Pleased with this coincidence, and happy with the idea that I can use 1920s rules to slam future seasons that get shrunken, say, by a global pandemic, I am dealing with this issue by ignoring it.
Ending an Anti-Dynasty
All good things must end—and all bad things, too. Because we're being open-ended with our definitions of how long a run can last, we need to define just how runs come to an end.
As we mentioned before, your dynasty points can't go below zero. If a team has a season big enough to wipe out their full run of anti-dynasty points, they get set to zero and the endpoint is defined as the last year with a losing record; the last year they gained anti-dynasty points.
The other way is to simply have two non-losing seasons in a row. We do allow for the occasional fluke season to slip through—the Browns going 10-6 in 2007 is not enough to completely wipe out the pain beforehand, and even a team as hopeless as the modern Jaguars can occasionally make an AFC Championship Game in a year where everything that could go right does. It is "non-losing" and not "winning," so an 8-8 season counted as a strike here. Get on the right side of the ledger two years in a row and all previous sins are forgiven.
These definitions are simple, but they bring up three problems—one theoretical, one dismissible, and one aggravating.
The first is that while two 8-8 seasons are enough to end an anti-dynasty, alternating between 9-7 and 7-9 years are not, despite the two teams being of arguably similar quality. I'd argue that there's a bigger psychological hit from dropping below .500 then there is for any other one-loss change. In addition, this has literally never come up—none of our 58 teams have artificially extended their runs by bouncing between seasons around .500. Generally speaking, if you're bad enough to rack up 30 anti-dynasty points, you're not going to be hovering around 8-8 for much of the time.
The second problem is that the same quality season might kill one anti-dynasty and let another one survive, depending on how long a team has been struggling for. An 11-5 season is worth -36 anti-dynasty points. When the 1992 San Diego Chargers went 11-5, that was enough to completely clear their record; they had 33 points going in, and zero coming out, bosh. But the 2020 Tampa Bay Buccaneers just went 11-5—heck, they went 11-5 and won the Super Bowl. But their ledger is technically not cleared yet; they had 44 points coming into the season and so 11-5 was not enough to completely clear things out by itself. One could imagine a team sprinkling in occasional 11-win seasons and totally gumming up their stats. In practice, however, only 24 of the 523 seasons covered by the anti-dynasty teams had a winning record of any description, and only one is 11-5 or better and enough to kill a small dynasty. Generally speaking, if you're good enough to win more than 65% of your games in Season X, you're going to be good enough to at least go .500 in Season X+1.
That leaves us with the aggravating problem, the case where both of our previous problems collide. What if a team bounces back and forth between winning and losing seasons, but those winning seasons are 10- or 11-win affairs? There are three teams that fit that description, and thus rank lower in the table than they probably deserve. Two are buried fairly low on the totem pole; whether a team finishes 35th or 32nd is not, ultimately, a major issue. But the third team, and the one that caused me to tear out my hair, was the Jim Schwartz/Jim Caldwell Lions. No one would argue that the 2001-2010 Lions were not one of the worst teams in history, and they grade out accordingly. But from 2011 to 2015, the Lions went 10-6, 4-12, 7-9, 11-5 and 7-9 before finally sticking above .500 for multiple seasons. That 11-5 season, in particular, is frustrating; it's the best record for any team on the rankings, but the 2000s Lions were so bad that even -52 points of playoff seasons isn't enough to completely wipe out the damage caused by 0-16. For most teams, adding a mediocre year or two at the back end of a dynasty boosts their case by extending the dynasty, but the Lions' average DVOA is hurt enough by those good years to be noticeable. For the moment, I'm just going to let that stand as is, rather than create a rule just to fix the Lions, but if the Buccaneers crater this year, I'll have to rethink that if I ever revisit the project. I just need Jim Schwartz to know that I hate him and his teams are mucking up my model, thank you very much.
That's enough methodology. You're here for the big table with all the teams in it, I'm sure.
The NFL has existed in its current form for 101 years. In that time 58 different teams earned dynasty scores of at least 30 points. The following table lists them all. It includes the number of seasons each era lasted, their high point in anti-dynasty points, and their win-loss record. Then you have their last-place finishes, including conference and divisional worst for modern teams. Finally, you have their DVOAs—both the average across the entire run of the era, as well as the average of their bottom five seasons. We remember terrible teams by their low points, after all, so that last column gives a better look at which teams failed the hardest. Teams with runs of less than five seasons have 0.0% seasons added as needed.
You may also notice that DVOA only goes back to 1983, and yet a little over half of the teams on the list predate that. To fill in these gaps, we go to two sources. A few years ago, Andreas Shepard produced estimated DVOA for all seasons from 1950 to 1982. This has a correlation of about 0.95 with actual DVOA, so that's good enough as an estimate for team quality back through the era of free substitution. Before that, we don't even have enough data to run Shepard's estimations, so we instead use Pro Football Reference's Simple Rating System—a rating that takes into account average point differential and strength of schedule, both of which we have going all the way back to the beginning. In recent years, it has about a 0.90 correlation with DVOA, so we can use that as a rough guess of team strength in the earliest days of the league. When you start talking about "average performance" in a league where teams fold, merge, and form at the drop of a hat, you're getting into murky waters anyway; this is about as good as an approximation as we are going to get.
|NFL Teams With 30+ Anti-Dynasty Points, 1920-2020|
|1968-1986||New Orleans Saints||20||118||90||196||5||0.318||2||5||10||-12.7%||-27.9%|
|1983-1996||Tampa Bay Buccaneers||14||95||64||159||0||0.287||3||4||11||-24.4%||-35.3%|
|1948-1958||Green Bay Packers||11||74||37||93||2||0.288||2||2||5||-19.6%||-33.6%|
|1971-1983||New York Giants||13||66||61||124||2||0.332||1||3||6||-14.1%||-25.7%|
|1967-1975||New England Patriots||9||58||37||88||1||0.298||1||1||4||-23.5%||-34.3%|
|1987-1996||New York Jets||10||50||54||104||1||0.343||2||3||5||-11.0%||-22.2%|
|1959-1965||Los Angeles Rams||7||49||25||65||4||0.287||2||2||3||-8.4%||-11.5%|
|2011-2019||Tampa Bay Buccaneers||9||44||49||95||0||0.340||1||1||7||-11.9%||-24.6%|
|1970-1977||New York Jets||8||43||37||75||0||0.330||0||0||3||-17.6%||-24.6%|
|1989-1995||New England Patriots||7||42||35||77||0||0.313||2||2||2||-25.6%||-32.9%|
|1997-2003||San Diego Chargers||7||42||35||77||0||0.313||2||2||6||-13.0%||-18.8%|
|1973-1980||San Francisco 49ers||8||41||39||79||0||0.331||2||2||3||-7.9%||-15.7%|
|1970-1976||San Diego Chargers||7||37||30||63||5||0.332||1||1||4||-15.7%||-20.4%|
|1974-1979||Kansas City Chiefs||6||36||28||60||0||0.318||1||2||4||-13.1%||-15.2%|
|2003-2010||San Francisco 49ers||8||36||46||82||0||0.359||1||1||2||-23.4%||-34.3%|
|2016-2020||New York Jets||5||34||23||57||0||.288||0||2||4||-23.8%||-23.8%|
|1973-1980||Green Bay Packers||8||33||42||72||4||0.373||0||0||3||-13.3%||-19.4%|
|1976-1980||Tampa Bay Buccaneers||5||33||22||53||1||0.296||2||2||4||-25.0%||-25.0%|
|1983-1991||San Diego Chargers||9||33||55||88||0||0.385||0||0||5||-5.1%||-11.5%|
|1994-2001||New Orleans Saints||8||32||49||79||0||0.383||0||2||3||-12.8%||-20.6%|
|2015-2018||San Francisco 49ers||4||30||17||47||0||0.266||0||1||3||-20.3%||-16.2%|
A wretched hive of scum and villainy, to be sure, and a pretty thorough accounting thereof. There are some individual terrible teams that don't make the list; no 1991 Colts or 2012 Chiefs to be found here. But if you're looking for the most painful stretches of football the last century has ever seen, they're all here.
The question now becomes how many anti-dynasty points are needed to really claim that your team is especially bad, and not just going through a run-of-the-mill transition. As always, we've gone for the big-tent approach—our net is cast wide enough to catch anyone who might conceivably qualify for worst-of-the-worst status. Where you draw the line between a generational disaster and just a run of poor luck is subjective. If you consider all 58 teams worthy of the title, that's an average of five or six teams in any given season fighting through a historic run of bad times. In 2005 and 2006, you had the Browns, Cardinals, Rams, Lions, Raiders, 49ers, Texans, and Bills all going through their own tough times—that's a quarter of the league. Would you really suggest that a full fourth of the league at any given point of the time is notably, historically terrible?
If, on the other hand, you're a small-tent guy, you might want to draw the line at 70 or 80 points, so there are only one or two anti-dynasties active at any point in time—if there's only one champion, there should only be one anti-champion. Symmetry and all that. The Jim Tomsula and Chip Kelly 49ers were bad, but the Hue Jackson Browns just shake their head and sigh. If you've only been bad for a handful of years, hope springs eternal. Spend too long watching the Clevelands and Detroits of the world, and that hope gets beaten out of you—maybe that should be the dividing line.
Barring a metric for determining a fan base's hope, this ultimately comes down to personal preference. I don't view this as a binary yes/no thing; it's more of a gradual trend from unprecedented laughingstock down to more questionable candidates. If I had to draw a strict line somewhere, I think I would put it in the mid 50s, right between the early 1970s Patriots and late 1960s Steelers. While that leaves out a trio of decade-long disasters, that's the point where teams start flipping from "man, we've had a run of bad luck for a while, here" and "can't wait to see how we blow it this year." Putting the line there gives you two or three teams at the bottom in any given year and that does feel more or less right—but I prefer a gradient.
So, we have our list of anti-dynasties and near-misses. But we promise not just a list of teams from most to least anti-dynasty-esque. We said we were going to use DVOA to rank them by quality as well. We'll do that, as well as go deeper into the ins and outs of every team on this list, over the next few weeks—a deep dive into the most terrible franchises to ever take to the gridiron.
Alright, let's explain some of the choices up there, and exactly what does and does not count.
First of all, the anti-dynasty list raises a question that the dynasty list never had to deal with: what counts as a franchise? There are a number of teams in the 1920s and 1930s that can be linked together through franchise transfers and contract buyouts. You have merged teams in the 1940s due to World War II, leading to vastly different rosters and situations for teams. And if you start picking nits, maybe teams should be considered separate when they significantly relocate; were Phoenix fans particularly concerned with the fate of the St. Louis Cardinals before they moved? We need some guidelines to keep everyone straight.
I went with a three-legged approach. For a franchise to maintain continuity, it needs to keep at least two of the following three traits: personnel, identity, and fanbase. If your team keeps at least two of these, then they count as the same team. Sell all your players and bring in an entirely new roster for the next season? You're still the same team—heck, that's practically what this year's Houston Texans are doing, and no one claims they're a brand new franchise. Rebrand yourself? Well, no one's claiming the Washington Football Team is a brand new franchise just because they've changed their name. Switch fanbases? That happens every time a team relocates, but we're not calling the Oakland, Los Angeles, and Las Vegas Raiders different teams; there's enough continuity between them to count. But when you have a situation where the owners of the Dayton Triangles sold their franchise to some businessmen from Brooklyn, who then bought a second team and imported that roster to their new team, and rebranded the whole thing as the Brooklyn Dodgers? Sorry, that's too much change for my book. Similarly, we're counting the Baltimore Ravens as a new franchise—very few of their new fans in Baltimore were particularly concerned with how the team was doing in Cleveland before 1996, and they make no claim to the Otto Graham-era history; if anything, they're more likely to claim Baltimore Colts history as their own. New franchise, new start, no carryover.
You may notice this leaves one problem: the New Browns. We have them listed as 1999-2019, but under the rules we've laid out, the 1995 season should get tacked on too; a vestigial lump of Belichickian failure grafted to the more coherent history of the reborn Brownies. And you know what? You're right—by the strict definition above, the 1995 Browns should be included, bumping their anti-dynasty points to 125 and further cementing them as the top team on the table above. After all, the Browns never stopped existing—part of the agreement when Art Modell left town was that the Browns would resume play in 1999, be it by expansion team or relocated franchise. And you could make a strong argument that the fans hurt by the 1995 Browns were the fans hurt by the 1999 Browns; Brownie fandom didn't go anywhere during the three-year interregnum.
And, in fact, I did make a number of those strong arguments, but ultimately, Football Outsiders traditionally considers the Old Browns and the New Browns to be two separate franchises. And, since the Browns are in first place on this list whether or not you include 1995, and they remain in the same position in the ultimate rankings whether or not you include 1995, it's sort of a moot point. No sense going to war over whether the Browns should have a winning percentage of .303 or .302. Arguments about whether or not this is typical FO protection of the legacy of Bill Belichick can be made in the comments.
When it comes to counting last-place teams, I'm not using tiebreakers. Fans of the 2015 3-13 Cleveland Browns generally did not think that man, it was a tough year, but at least we had a better strength of schedule than the 3-13 Tennessee Titans. The league may only crown one champion, but there's plenty of room for multiple teams at the bottom. The same is true for conference and divisional last-place finishers when applicable; the 2018 Raiders and Jets can share the title of worst team in the AFC at 4-12.
Before 1972, ties were not counted in the standings. We are retroactively counting ties as a half-win for the purposes of winning percentage, but we are not counting them when it comes to determining last-place finishes. The 3-9 1947 Lions did not consider themselves tied with the 2-8-2 Giants at the bottom of the league standings, and we're not going to try to make them feel bad about that 75 years later.
The merged World War II teams count for both teams involved: the 1943 Steagles are both the Steelers and Eagles, 1944 Card-Pitt is both the Steelers and Cardinals, and the 1945 Yanks are both the Tigers and Yanks. Two of those teams feature prominently in the countdown; the third throws some interesting wrenches.
Both the NFL and AFL count for this list, but no other leagues—no AAFC, no USFL, no CFL, no WFL, neither XFL. The NFL does not consider the AAFC part of its history despite the 49ers and Browns coming from it, so rest easy, Chicago Rockets—you escape. For now.
No system is perfect, and this one is no exception. Trying to figure out how to compare the ragtag teams of semi-pro high school kids of the 1920s to lumbering, overpaid sloths of 2020 is a ludicrously difficult task. There had to be some accounting for teams that played a handful of games and then exited the league. If we took every record at face value, and prorated them all to 16-game seasons, then the greatest anti-dynasty of all time would be the 1920-1921 Muncie Flyers. The Flyers played three AFPA games over two seasons, losing 45-0, 14-0 and 14-0, and putting up estimated DVOAs of -106.1% and -88.9%. Calling them the worst team of all time, while probably factually accurate, is uninteresting—obviously, a semi-pro team occasionally dabbling against pro teams is going to be bad. That's not interesting, other than as a brief footnote. In fact, if you don't prorate things at all, the top 10 would be entirely terrible 1920s teams—the 1-12 Louisville Brecks would be make the table, the Minneapolis Marines would be fighting for the very top spot, and so on and so forth. Writing about seasons in the 1920s and trying to give it Football Outsiders-style analysis would actually be a heck of a fun side project, but a top 10 of teams most people have never heard of, much less seen, is not a fun way to end a list like this.
There was a lot of trial and error trying to handle teams with partial seasons from the days of the single wing—adding arbitrary games of .500 ball, prorating different seasons of different lengths at different weights, and so on and so forth. Ultimately, counting any team with single-digit games played as only worth partial credit ended up producing the most aesthetically appealing list, and had the added benefit of being simple. It does mean that the 1920s and 1930s teams included aren't really the worst teams of their era; they're just the worst teams that were well-managed enough to stick around. It seems rather strange to be applauding teams for making a list of terrible franchises, but lasting long enough that we can get a relatively accurate picture of just how bad you actually were is an accomplishment. A bad one, but an accomplishment notwithstanding.
The teams that made the dynasty list were pretty spread out over the history of the league. There's always a champion, after all, so someone was racking in the maximum points, regardless of whether they had to beat seven other teams to it or 31. But there's no limit to how many teams can be horrible in any given season! Because we have the same number of teams on both lists, that means that the anti-dynasty teams are roughly evenly spaced after adjusting for league size. At any given point, roughly a quarter of the league is on the list. That means we're weighted more for modern teams than we are for classic teams, because a quarter of 32 is a larger number than a quarter of 12, mathematically speaking. I'm alright with this in the long run, but it's worth keeping in mind. The NFL didn't suddenly gain a bunch of terrible teams when the 1970s expansion happened; they simply had more teams which had the possibility for terribleness.
That being said, there are two eras which stand as being particularly loaded with entries. From 1933 to 1939, there are four anti-dynasties in a league with only 11 teams or less. From 1970 to 1975, there are 10 to 12 active anti-dynasties in a league with only 26 teams. That's a lot, but those might well be the two eras with the least parity in the history of the league. By the 1930s, teams had settled down enough so that they weren't folding left and right, but rules to attempt to keep a fair playing field throughout the league hadn't been invented yet. The Great Depression meant a number of owners tried to cut costs wherever they could. There wasn't a common draft until 1936, so bad teams had to try to outbid the wealthier and more established Giants, Bears, and Packers for talent. The idea that the league would give bad teams extra help to one day become good teams wasn't really a concept, and so there were massive gaps between the haves and have-nots. As for the 1970s, that was the era when dinosaurs roamed the league. Between the Steel Curtain Steelers, the America's Team Cowboys, John Madden's Raiders, the Purple People Eater Vikings, the 17-0 Dolphins, and so on and so forth, there just weren't many wins to go around for the bottom-feeders of the league. For every team winning 80%, 90%, 100% of their games, someone has to be losing in large amounts. I'm alright with the 1970s being overrepresented here; it was a terrible time for competitive football on the whole.