I am not sure that most players stop when they are winners because I have different experiences when I visit casino. There I have met people who if they win they don't stop because they believe that it was their lucky day and they have not to kick off their luck. But as all we know it is only stupidity, a vast greed and nothing else. On the other side when I lose I always fear that I will lose all of my budget or somebody steals me and so on. Thus, I gradually decrease the bets and finally I stop even I feel bad