When are you a loser?

[CardMinger]

I know this might have been asked before but I never exactly have read it being asked in this manner.

I have heard in numerous posts that by playing just around 100 SnG's of a certain limit you should be able to tell if you are a winning player or not...does the same apply for if you are a losing player?

When is it time to give up and quit, move down or re-evaluate your play?