Despite their Confidence, most true villains are pretty darned humble, so humble that it gives me a special glow all over. Take, for example, the original bug-eyed bandit, Kanjar Ro:
"Ah! My super-brain now understands all the mysteries of nature and the universe!"
Kanjar Ro, "Decoy Missions of the Justice League!"
Okay, Kanjar Ro may not sound particularly humble. But consider: a guy from some distant planet suddenly acquires an understanding of all the mysteries of nature and the universe. Which is a lot. Yet instead of using those powers to end suffering on a thousand planets, earning the grateful devotion and love of every sentient being he encounters, and making himself the most exalted creature that ever lived, Kanjar Ro chooses immediately to humble himself by 'sailing' to Earth in his moronic-looking cosmic boat to have his hiney whooped by the Justice League.
The more impressive and powerful you are the more important it is to be humble; but, of course, that's one of the mysteries of nature and the universe that Kanjar Ro understands!