The amount of winnings considered sufficient (per day) depends on the initial capital I deposit. Like it or not, I have a calculation for example if I deposit $10 and manage to turn it into $30-$50, it means it's time to withdraw. Personally I set these limits so that I can gamble more sensibly.  But I won't deny that there are certain moments when the winnings haven't reached the target but I have to make a withdrawal to end the game.