As I said, it's not always and the chance is slim so when you see that chance better to grab and quit your way to enjoy the amount that you earned.
You are absolutely right, when I won many times I didn't even enjoy the money, what I did was invest it in playing and playing again, and I didn't see anything, in the end I would leave the money I won back in the casino, and this taught me that when you win in a casino even if it is a little you have to withdraw it, you have to enjoy it, you don't have to hesitate or leave it in the casino, you can leave 20-30% if you want but you have to feel that money in something, see that the effort was worth it, so in view of this, you always do the best you can, it took me time to reach those conclusions , only experience got me there.
The best teacher at all time, your own experience gives you the hint whenever you needed to stop, either you already have enough to withdraw or you needed to pull that string to make a hard stop avoiding to lose a lot, gamblers always look for the best way to win and enjoy that's the reason why they are using or creating patterns and strategy in hope that it will gives decent chance of winning.
Even how small your earnings as long as you are in green that's still profits to add on your initial deposit, taking it out from the house considered as winning amount and the strategy that you use works well for you.