[inimino]

Update: the first paragraph above was not quite right for the system described here. It's more about the EV calculation involving ever growing outcomes multiplied by ever shrinking probabilites, with the mean still growing without bound, while in any cohort of practical size you'll never see any of these outcomes. So it's not necessary for any player to go to zero to see the behavior. Of course there are also martingale systems that work the other way and they are also non-ergodic.

So in fact regardless of the initial run of luck, every player still goes to zero with probability one. The youtube video that another commenter linked to actually explains the 40% and 50% example much better.