All sorts of different things motivate people to do things - and from a storytelling standpoint, if you can take a character that's grappling with issues in their lives and sort of force them to deal with them, that's a great source of drama. For me, that's why it works so well. It's because you're taking a character and forcing them to confront things in their life. And I think that's a great inspiration for a story.
Ben Wagner