These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Don't forget about Madden 95 and 96 actually having the NFL on Fox theme music!
Complacent Gaming Syndrome: In every iteration, there is usually one team that is considered the best and attracts the majority of players. Commonly, this is a team with an elite defense and at least one dominant receiver. In Madden 13, San Francisco fits that bill.
Game Breaker: Some plays will always work, no matter what defense is called, because they exploit holes in the AI. There has been an enormous Internet argument raging for years over whether this is appropriate play or not.
Some teams are so insanely good that it is nearly impossible to beat an experienced player who decides to use them against you. The Falcons in Madden 2004 are the most infamous of them, but any Colts team that includes Peyton Manning is going to be this from year to year. Time will tell if the Broncos in Madden 13 will be the same.
The Hall of Fame edition of Madden 12 also comes with some of the most infamous game breakers in series history included as a special bonus.
Good Bad Bugs: Depending on whether you're using them or being victimized. A short list includes Rocket Catching (the wide receiver gets a speed burst to catch the ball), Jetpacking (the WR jumps several feet in the air, higher than their ratings deserve), or the WR snap glitch (The center snaps the ball directly sideways to a wide receiver).
Don't forget the Aaron Brooks glitch.
In one roster update, the developers mistakenly listed one player as 6 inches tall instead of feet. He was still able to interact with the rest of the players as if he was full-sized, which led to some hilarious animations.
The ambulance in John Madden Football '92, which can end up inadvertently running over other players while tending to the injured player.
Hype Aversion: Madden is undoubtedly the single most popular multi-platform franchise, but there are some people who will refuse to play it precisely because of that popularity.
It's the Same, Now It Sucks: Just about every game that has only token gameplay changes over the last installment. The game has essentially fallen into Broken Base territory, with many people complaining that the game is too similar. But since people have been playing virtually the same game for ten years, there would be a significant backlash if it changed. Furthermore, some Madden veterans hold that this is complaining about games you don't play, since those seemingly "token" changes can have significant effects on the Metagame, much like in fighting games where hit boxes and special-move priority are undiscovered by non-hardcore fans but are vital to high-level play. And, of course, there are only so many changes that can be made to something based on a real-life game with a concrete set of rules and play.
Just Here for Godzilla: This game is so popular that there are a not-insignificant number of people who buy game systems just to play it, and never play anything else.
On the flip side, the pre-order bonus for the $100 Madden 25 Anniversary edition was a yearlong subscription for NFL Sunday Ticket. Which usually costs $300 + a Direc TV subscription on its own. Many people bought it just for Sunday Ticket and promptly sold the game itself.
Whenever a real-life NFL player makes a big play, it is now customary for someone on a forum to say that "PLAYER X PUT DA TEAM ON HIS BACK DO"
Misblamed: 2K supporters tend to blame EA for buying out the NFL license as a way to kill 2K's series. In reality, the NFL put up the license exclusively for sale as part of a movement to solidify all their merchandise under one individual company per medium, and it wasn't like EA was going to lowball an offer for their most lucrative franchise...
Scrub: A long-running debate among fans of the series is how much players are expected to hew to real-life football strategy (punt on 4th down, no unnecessary 2-point conversions, etc). Some versions of the game actually have an optional toggle that bans these types of strategies.
Similarly, some features have an annoying tendency to disappear between iterations, leading some to suggest that they are being deliberately held back.
They Just Didn't Care: The only explanation for the continued injured reserve bug is laziness or apathy. Apparently fixed in Madden 12, though hackers found a workaround for earlier versions.
Unfortunate Implications: In Madden 11, the winning Super Bowl team is shown visiting Barack Obama at the White House in a postgame cutscene. However, this same scene would play with Obama no matter how many seasons the player ran through - showing that Obama apparently seized power in perpetuity in the Madden-verse.