As the questions says, when do you stop? your point of no return?
a. at least double your money, then stop
b. you only stop when you have lost all your bankroll money and then blame the casino?
c. or you are a superstitions gambler, when you have signs like losing 3 straight in a row, then you quit because you know that you're having a bad luck
d. you stop when you are at least break even
I didn't include chasing your losses as obviously you might to continue.
I always have a loss limit and a win limit, which keeps me consistent and prevents me from engaging in negative behaviors like chasing losses, etc. This way, I can always be familiar with what to do when my losses reach my predetermined limit and decide to stop. I also stop betting once I feel my winnings are more than enough, or at least reach my predetermined limit. So, none of the options listed above are suitable for me, as I believe the list you provided is simply a general plan that every gambler follows.