That's the reason why having "enough" is important for a gambler. Because for people who do not have a sense of “enough” in themselves, they will always feel deprived even when they have won a lot. They will always be driven to continue gambling and get more money, because in their minds it is not enough and they are very eager to get more. What happens is that most of these gamblers lose money that they could have withdrawn if they understood the meaning of the word enough, and in the end they will only blame the situation where they become unlucky.
This concept of knowing when to stop may preserve many a person who wants to ruin his/her own earnings. Greed is also one of the greatest pit falls to gambling as it causes you not to think of the risk but only the need to hunt more. I have witnessed people who have won all the amounts of money and yet they have gone home empty because they did not know their limits. The thing is, not every time it is the lack of luck but rather their mentality which does not allow them to stop when they are leading. It is not easy to thrive in gambles in the long run; one has to have control over him/her.