The full responsibility for the fate of your company, and all of the people depending on it, though it depends to a great extent on investors, partners, customers, the markets, technical and social and financial risks that you can only vaguely see and barely control, ultimately rests on you.<p>This is so completely unlike the typical modern day human experience that people often just get culture shock and flicker out. Even more often, they give up and fade out, blaming some little thing or external cause for their failure.<p>The creation of valuable new technologies, while challenging, seems like a cakewalk compared to the moral weight you're required to bear when running a company. I think this can be partially seen in how many entrepreneurs do end up giving up the reins of their company; either during an acquisition or to 'professional managers' (who often themselves simply shirk the moral weight since the company isn't theirs to the same extent.) Those who can take their company to the next level are, at each step, both rare and exceedingly valuable.