Yes , usually we set up a limit for ourself, but most the time we break it and lose more than becoming angry and keep chasing the loss. So it's not good at all for a gambler.
Well for me as my reason on what is the best time to stop especially in gambling is when you attain the most higher value of the gambling prices, and if your'e lose and don't have enough money or any token maybe it a time to quit for your own safety. Sometimes some gamblers do this kind of strategy where in it is good to them in order to have more winnings, came back on another day to gamble.