St. George Slaying the Dragon, Hans von Aachen
I honestly don't know why. As a reader, I hate reading about someone like that. I don't want to read about someone who just goes around doing bad things (murdering, for instance); that's not a person I want to get behind and cheer on. I certainly don't want to be manipulated into somehow liking this person that I would never like in real life.
I have no problem with a villain who has some sympathetic traits. A completely evil villain can get dull. Someone morally complex, but also recognizably bad so that we can cheer when he is defeated, is much better (though I don't write off all villainous villains who only have money, or power, or revenge, in mind).
So, going from that to a hero, what is a hero?
I think we often get sucked into the trap of believing that a hero can't be awesome unless he's flawed and conflicted. I definitely think we should work on our heroes, for the most part, being realistic. But then, sometimes I just get a craving for a good old fashioned hero who may make the wrong choices (or not), but who is unflinchingly good and virtuous, who defies evil just by existing.
I find myself writing more complex (I hope) heroes and villains, but I think I, and a lot of people, will always be drawn as well to the archetypal good guy, the one who may be unattainable in his goodness but who draws us to him just by virtue of the fact that he is the opposite of evil and can always be relied upon.
For a Christian, saying that a perfectly good, moral character is always boring and one dimensional obviously ignores the fact that Jesus himself was neither boring nor one dimensional.
And anyone who says that a villain can never be pure evil apparently forgets about the Devil.
So really, what I'm saying is that as usual you can't say, "Here's how to do it, and otherwise your story will not be awesome."
(I do, however, think that just about every superhero ever invented is boring. Your mileage may vary.)
And one more thing, re: anti-heroes, is that I don't have a problem with a character who starts off as a villain and then changes. I love seeing a bad guy wrestling with his conscience and slowly beginning to turn from villain to hero. I just don't want the main character to be the villain all the way through, especially if he's against a good guy.
What are your thoughts on heroes, villains, and anti-heroes? Are there exceptions?