I think many gamblers set "double deposit" as their minimum goal. Even though those who gamble for fun, when they double their deposit, they start to think about making a withdrawal. I look positive on having such goals. And there those who "wont leave until they get a high multiplier or win jackpot". Such kind of goals I dont recommend anyone to have. Gambling without a goal, that is a rare thing to see today. I rarely see those who prefer gambling as a time killer.
It seems to me that those who play for fun will not withdraw their deposit. Even if they set a goal for themselves like doubling their deposit they will not cash out. When they reach that goal they will just set a new one and keep playing. And those who aim to hit a jackpot will probably not withdraw either no matter what goals they achieve. It reminds me of traders who can turn small amounts into millions and then a few weeks later go back to zero. It is a kind of submission to excitement that is very hard to escape. You always want more and more. So if you don't set a clear goal for the amount you are going to withdraw most likely everything you win will stay in the casino and eventually turn into losses.
Those who gamble for fun anyway have their limits. They cant change goal again and again. There will be a moment when greed factor comes into play. No matter how they convince themselves that they gamble for fun and money is just a paper, they will face a moment when they will consider pity to lose such an amount. I believe that those who gamble for fun withdraw their winnings, but compared to other gamblers, they gamble more risky, more reckless, more careless, more spontaneous.