The best choice has always not been taken by many gamblers when they are in green not until when they start getting series of reds with each bet going further that's when they get back to their senses to wishing they had thought about quitting while they still had so much in hand to leave with. Insatiate behaviour is an enemy every gambler should deal with, if not, they will always lose all after any little win.
That's what always happens, it's happened to me, to understand that one must stop is when experience says it, it emphasizes it, because money must be taken care of and when you earn it you have to value it, it's luck in the end, but to get that luck there had to be a previous effort, even if the effort was very minimal, those things must be valued.
Experience could be helpful in making us give value to the little profit we might have gotten from the little win. But for those gamblers so greedy for huge wins they find it very difficult to give value to those small wins they get and that makes them to throw in back the little profit they could have walked away with to later come back another day to try again. When I see gamblers do this, I just conclude that they are not appreciative of their luck in the little size it comes except it has to come huge. Whereas, there are those that are just praying to earn same little luck for such small profits but they just not earning it still.

Every gambler has a target or an idea of the amount of money they want from gambling, and if such a gambler is spending the right amount of money to earn the amount of money he or she is hoping to earn from their gambling activities, but the supposed amount isn't forthcoming yet, we can't call such a gambler greedy if he is she decides to invest back to gambling the little amount they earned since this is not the amount of money they are looking for...
Understand that as humans, we all are created differently and with different desires and priorities, this is why when it comes to finance, we have the rich, the middle class, and the poor, humans can never be equal in terms of several things like desires, priorities, financial wants and needs and so on..
So if you are gambling and you always appreciate every small win, that's you, don't expect the next gambler to also do the same, you want and what you appreciate may be far different from what he wants and appreciates.