Job hopping for a founder or CEO would be an entirely different thing. If you take someone's money, you take on responsibility to them. If you personally hire people into a position that won't exist if you abdicate, the same is true. If you hit a patch of shitty or painful work for a few months, you stick through it because other people are depending on you.
Someone who tries a corporate job for four months, realizes that he isn't getting good projects, and leaves, is (a) doing what he should do, since he's undervalued in his current role, and (b) not really hurting anyone.