There is no need to wait for a certain age. We can retire at any time. Besides, this is not a job, not even a business…it depends on us when.
However, I see a lot of gamblers separated from the gambling world, not because they want it but because they can no longer perform the task anymore. They were already paralyzed due to an accident. And I cite this example because a gambler won't easily get out of gambling like she/he wanted to. Mostly because they can't do it anymore, even though they still want to. There is always a reason behind retirement, and I can have one too someday. I don't know yet.
I have said these before that gambling is not a job opportunity whereby someone will know when is due to retire, what you said is the best opinion so far, gambling is game of profit and loss, if you lose its of your detriment and if you gain its of your detriment, but the most important thing in gambling is that, know what you can afford to lose, because wining and losing is something you can't predict accurately, retiring in gambling is a decision taken by a gambler, it doesn't have to do with age, so i believe that in gambling if we the gamblers understand that gambling is not a job, we shall not be willing to know when to leave gambling or not.