My greatest weakness for table-top roleplaying is that I always want a bit of dialogue with a proper story behind my character. If I don't have those, then I have a very shitty unorganized character sheet, I always want to say something, and I do stupid things. This is right now happening in our current Pathfinder campaign and I'm thinking about retiring my man. For plain old roleplaying, it's that I get bored with the roleplay because it either dies, the topic/genre becomes uninteresting or the story never changes. No proper plot, just the exposition over and over again.