Most gamblers aren't lucky, but let's say they have had lucky moments. The truth is, in those lucky moments, we lose the money we won to get even more, not to withdraw it. Each of us has experienced such significant losses. Actually, it's not the loss itself, but the profit, the inability to withdraw what we earned. After that, you can't rest until the money is zero.
When the money starts to dwindle, you crave that winnings, and the little you have left is always the same story. Those who can stop and withdraw are good and have developed a good level of self-control. In my opinion, stopping and withdrawing isn't something everyone can do.