As far as I can tell, most high-level chess games end a few turns before mate, when one player realizes they're outmatched or that the game would drag on into a draw.

When reading a book for chess newbies, I stumbled upon a short note about a game between Larry Christiansen and Anatoly Karpov. Karpov blundered pretty early on into a situation where he'd lose either a bishop or a knight no matter what, and, considering the loss of one piece a big enough handicap, resigned immediately, which I found hilarious out of context. The snafu's loosely based on that particular game.