I stop playing after I double my money to resist the temptation and not lose all the money.
Its good because if you play again there is a possibility that it may lose then you play again to have profit if lose you have nothing left at all .Sfter doubling or tripling the profit it is enough not to push your luck to crash.
But most of the addicted gamblers they can't control themselves even after doubling or more they will surely come back to gambling with that winnings and lose back to the site. Unless they just take out that money and come back only after few days with the smaller amount then they can save some money. It all depends on how one is addicted to these games.