In AAA you work just like anywhere else, except you're subject to frequent and sudden changes from above. So you're working on something for months, only for some retard from management to come, play with it for five minutes, and tell you that the whole thing needs to be scrapped and done again because he doesn't like it (and then he'll proceed to tell you how it should look usually in words such as "Do it like in [Big AAA game that sold shitloads]"). Since there's much more distance between everyone (both due to a much bigger team and due to a much larger hierarchy of the company leadership), this sort of shit happens way too often. Alternatively, after working on something for half a year, you'll learn some other part of the team is lagging behind too much (usually because management came, demanded adding a new feature, and didn't change the deadline), so all your work is getting cut, that sort of thing.
Do you know the Mafia series, for example? Both of these things happened during the development of Mafia 3. Art team had been working for months on an entire city (I think it was Havana? Not sure) and actually had it pretty much ready, massive as it was... only for the whole thing to get cut. Ouch. Many among the art team quit after that. Or do you know the driving model in Mafia? Fun fact – in all three games, it was done by the same dude. He likes creating super complex and super realistic systems – in Mafia 1, there was no mechanic tailored to a specific car. Instead, he just created the system, into which design put car parametres from some car encyclopedia. And it actually worked, all the cars behaved precisely like they should. So he then improved on it in Mafia 2, and aimed to create the ultimate system in Mafia 3. And he did it, it was super realistic, gave you a real feel for the car. Then some management dude came, played it for five minutes, said he disliked the driving model (because, due to how realistic it was, you needed a touch of skill to drive well), and had the entire thing scrapped, telling the guy that he should create something more arcade-y for driving. And that's how you got the shitty driving model in Mafia 3 that everyone hates. The dude naturally quit the company afterwards as well.