It really depends on the type of villain for me. It can be fascinating to find yourself identifying with a villain--I like backstory with evil antiheroes, or tragic villains instead of just, well, villainous villains. But it has to be done right, or you wind up with something like, say, the Star Wars prequels. And in this case, the curiosity isn't so much about being in his head as just answering my final questions from back in the Chronicles--namely, "Did I miss something? What the hell was THAT all about?"

So, for someone like me, karjack's reason is the more compelling. Bad Writing may be enough to turn me off without the other reasons.