Agree with chico totally, fighting isn't marathon-running and there's no shame in quitting. There's a moment when you realize you've got nothing left or you threw everything you could and more at your opponent and it didn't work---after that, it's not a challenge anymore, just dangerous. i fuck around with gracie j-j in the winters a few times a week and since it's more or less drop-in, the skill levels vary,. you're not considered less of a man if you give up when someone has your arm in a position to break it at will-you're stupid if you don't. respecting when someone taps out/etc. is something i've never seen violated, anyone who does better be so good they never have to train, because people won't get near them.