Withdrawal of winnings isn't just the issue because you can withdraw your winnings and then still put the money back in it again because maybe you actually didn't use the money well the way it's supposed to be used. There are so many cases that have resulted to gamblers getting all addicted because of the lack of will power to actually make that decision of yours withdrawing their funds and using it wisely.
This is where the issue lies, it is not about whether you withdraw your winning immediately or not. What matter is how you make use of the money won. You can make withdrawal after winning and later end depositing more than what you just withdraw. The bottom line is knowing how to control your urge to gamble unnecessarily. If you can control yourself and maintain bankroll, you have nothing to worry about even if your funds are still in the gambling platform. You can play reasonably when you want to and make withdrawal when you want to. As for addict who can not control themselves, it's the same whether they quickly withdraw or not because they will in no time make a deposit instantly and even regret withdrawing in the first place.