Villains change the status quo. Heroes protect it.
Villains see the world not as it is but as it could be. They rail against what is. They lever their will against the world to change it.
Heroes protect what is. They see the beauty in the world, and they know the limits of an individual will. They seek to preserve the good and limit the possible bad.
Villain: “This fence is in my way. It says that I cannot go over there. I disagree, so I will tear it down.”
Hero: “You do not know why that fence is there, you should not tear it down. I will stop you.”
(Chesterton: “What are you doing to my metaphor! Let me out of this box!”)
This distinction is different from winners versus losers, by the way. If you’re a villain, it doesn’t mean you’re destined to lose. It just means the cards are stacked against you.
Hero and villain are terms decided by the present. Those who benefit from the status quo will always cast their protectors as heroes. Winner and loser can only be labeled after the fact. The winners write the history books, but the incumbents write the propaganda.