When do you stop? Do you have a daily limit or something?
I stop whenever my deposit already zero or when i'm too tired to play. If people used to use bankroll management and some kind of limit upon themselves, they will know how to stop and never cross the line.
Limiting yourself is the thing to do in order to know when we should stop. Limit your spending and overcome the amount of play. But all those boundaries will be useless if we break it or surpass it. Going beyond limits is what happens because of a lack of good self-control. Therefore we must first be able to control ourselves.