Jenny over at The Blackwing Diaries makes an excellent point about what passes for character development in far too many stories (be they prose, comics, TV, or cinema): the overcoming of the pointless character flaw. Somewhere along the line this notion that characters need to overcome a shallow flaw by the end of the story crept in, and it almost never works. I remember as a young kid watching Back to the Future II in the theater, and finding it jarring when Marty McFly suddenly had a problem with someone suggesting he was "chicken" -- a straw-man flaw he overcame by the end of the final film.
But the main problem was a very obvious and basic one: the character as presented in the story was unlikeable. He was selfish, rude--and selfishly rude, and a dozen other tiresome variations on selfish and rude. Apparently it was more important to the writers that we follow the adventures of a truly unpleasant character, supposedly identifying with him for 80 minutes, just so his story arc could have him redeemed at the end.
I don't know about you, but when I watch an animated film, especially one with rich potential for fun and high spirits and comedy, I don't want to be forced to either sit through a therapy session with a mediocre analyst, nor do I want to spend most of that time with a jerk. That doesn't mean that a character has to be perfect, or perfectly happy, or have no troubles. But there's been a trend in all types of film to insist that the character can't just face a conflict, he or she has to be terribly flawed and conflicted himself. It used to denote depth in a character. It's become a formula and it's an approach that needs to be handled with incredible finesse to work. Think that happens regularly?