If he can quit gambling after he wins a huge amount of money, then that will be the biggest winning for him because he can use that money for his life, and he can buy anything he wants while he can also saving that money for his future. I think it is reasonable to see someone quit their gambling activities because they don't want to ruin their life after they win big money.
But if that person comes back and tries to search for another big winning, I don't think that will easy for him because his biggest lucky already comes to him, and it is difficult to have another biggest lucky in the other days. His decision to quit gambling is the perfect decision for him while he has a chance to do that.