Rourke is the exception, cuz he really could have been a good actor. He just chose to dip into different professions and it hurt him. Especially the boxing thing. I read something on him a few months ago, and couldn't believe the things he could have cast for. It really blew my mind on some of the movies he could have been in, but screwed them up. Hopefully The Wrestler will be a wake up call for him.
