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I think constantly about the Frozen 2 behind the scenes series and how it confirms that there was no unifying idea for the story as late as 3 months before release and that the exciting trailer was essentially animated concept art to evoke a general feeling with no plan in place
You can see the way everybody is trapped by the creeping immovable deadline and the fact that it's being animated simultaneously to production, so there's financial and time pressure to work around the arbitrary nature of which scenes are farthest in production
You see them doing peer screenings and taking feedback on rough cuts of the movie, but the purpose of the feedback isn't really to strengthen the story as much as to figure out what needs to happen to make the movie coherent, because it's too late to aim for much else
The end result is a movie with one of the coolest aesthetics of any Disney movie and a couple really great songs (one of which turned out to be added a couple months before the film's release, and then nearly cut) but a lot of wheel-spinning and no lessons learned
