Iron Man, when Nick Fury showed up looking for Tony Stark, after the credits had finished rolling.
Since the first Iron Man was released, fans have become accustomed to waiting around for post-credits scenes, especially when they're seeing a superhero movie. And while the majority of people don't seem to think there's anything wrong with them, there are some who are definitely not happy about the post-credits scene's rise in popularity. Mangold is very much in the latter category, and he didn't mince his words when he was asked for his thoughts on the subject.
While attending Audi's 2018 Writers Guild Association Beyond Words in Los Angeles (via X-Men: Days of Future Past):
The idea of making a movie that would f***ing embarrass me, that's part of the anesthetizing of this country or the world. That's further confirming what they already know and tying in with other f***ing products and selling them the next movie while you're making this movie, and kind of all that shit that I find really f***ing embarrassing. Like, that audiences are actually asking for scenes in end credits when those scenes were first developed for movies that suck, so they put something extra at the end to pick up the scores when the movie couldn't end right on its own f***ing feet.
"Now we've actually gotten audiences addicted to a f***ing bonus in the credits. It's f***ing embarrassing. It means you couldn't land your f***ing movie is what it means. Even if you got 100,000 Twitter addicts who are gambling on what f***ing scene is going to happen after the f***ing credits it's still cheating. It's just cheating, but there's all sorts of bad habits like that that f***ing horrify me, man, that have become de rigueur in the way we make movies and I think the fear of being one of them that did that end then everyone's patting me on the back and I feel like shit inside because I know I cheated, is probably the greatest thing that scares the shit out of me."
Technically, there is nothing wrong with using stingers. At this point, it's simply regarded as something already part of the film and not a bonus scene, especially with Marvel offerings. And to be fair, not all films that have tags at the end are deemed bad. For projects that are part of a franchise, it's a different way of reminding people that what they have just seen is part of a bigger narrative. Other times, it's just a fun bit attached at the end of a movie. Moreover, it's a great ploy to keep people in their seats for the film's credits and learn to better appreciate just how many people actually worked on the movie that they just finished watching.
Then again, Mangold does have a point about the idea of a couple short credits scenes being expected to salvage the full two-hour film that just came before it. It's like studios are asking people to pay to watch a subpar movie and sit through the whole thing, just to get a short bit at the end that may or may not have a direct relation to what they just watched . Stingers shouldn't feel like they're consolations for seeing a film; if anything, they should be added perks for those who stayed until the very end of the credits roll.
