He generally only shows locks he knows how to pick. Unlocking is the payoff to the video and I don't think I've seen a single video where he didn't succeed, but if you read between the lines on his older videos, you notice him talking about the locks he recently learned to pick, locks he's never been able to pick, and so on.
He's very good, but he's not infallible. He just doesn't show his failures.
LockPickingLawyer has picked just about any and every single lock there is known to mankind. Would love to see him up against this!
Would make for some great content.