Which villain should just quit while they're ahead?

One thing you always know about great villains: they keep coming back. Again and again. But sometimes, a villain achieves such a masterstroke of evil, they ought to retire once and for all — instead of coming back with more penny-ante schemes. Which major villain ought to just declare victory and go home?

Please include a picture or video of this victorious evildoer. And mention his/her name, and why they ought to have left it after achieving perfection.

Top image: The Joker, who can never top his winning streak in the late 1980s.