So, here putting out the same question, what will make you quit gambling forever? A win or a loss, or both?
If you are gambling for money, you will easily be able to decide stop gambling when you win a big sum. You may also stop gambling with a very huge loss. But when you are a gambler who is gambling for fun, it will be another reason, something apart from a win or loss that will stop them and make them quit.
If you gamble for fun also and you win big It is possible that you change your fun activity to something else because you can now afford more.
First of all not all gamblers quit gambling after hitting a big win infact this would be a motivation for them to keep gambling because they feel like they can always get lucky. Gamblers that lose a huge amount are even worse on the scale, they tend to chase their losses by gambling more which eventually leads to them losing more money. It doesn't matter the type of gambler you are though all that matters is your decision, you can decide to make a change if you are intentional and consistent about it, as a repentant gambler I wouldn't even advice you to gamble for fun or engage in it occasionally cause it might trigger what you are trying to avoid.