There's nothing wrong to keeps playing gambling after winning but we must have good self control to holds ourselves to playing gambling excessively. There will be a tend to chase the big wins especially if our greediness increase and we can't stop from playing gambling. We must prevents to chase the big wins especially if we already wins before so we just needs to enjoy the wins money.
The winner will want to win more and the loser will want to get back the money they lost. Indeed, controlling greed and emotions in gambling is not easy and I don't see many people who will be able to do it.
I believe that most of us gamblers have a plan to withdraw money after winning big and leave a little to continue playing, this is quite a common plan. But one thing I see is that when people lose the remaining money, they tend to deposit more money to continue playing, so if we cannot control our greed, withdrawing money will not have much effect. So let's focus on controlling our emotions and controlling our greed instead of thinking that withdrawing money is a good plan, IMO.