No it wouldn't. It would cease to further incentivize them. Once you have enough money to live comfortably for the rest of your life, maybe you don't need external incentives for your behavior? Maybe you should be encouraged to simply do whatever you find most fulfilling, without financial reward?

> dis·in·cen·tiv·ize

> verb

> discourage (a person or course of action) by removing an incentive.

Regardless, though, how exactly would your proposal not prevent someone from building future companies? If stock is considered monetary wealth (the only viewpoint from which we have billionaires), they would be forced to... What? Give away their existing stock in order start a new successful company?