And Gates undoubtably let Ballmer stay at Microsoft too long. Ballmer should have been let go years ago.
Still, despite all that, now is not the time for Gates to leave as chairman. The transition from Steve Ballmer to the next CEO is going to be difficult enough; having Gates leave the company could leave it in chaos, and have partners, the rest of the tech industry, and company employees uncertain about Microsoft's future. That would make it more difficult for Microsoft to attract and retain top-notch employees and to make deals with other companies.
It would also make it harder for Microsoft to attract a CEO for those reasons. And there's no doubt that Gates would do a better job of courting and attracting potential candidates than anyone else on the planet.
Beyond that, Gates may no longer be involved in the day-to-day decisions at Microsoft, but there's no arguing with his brilliance. His mastery of understanding the nexus between technology and business is still unmatched. Microsoft needs his acument right now.
So no, it's not time for Gates to go. He is certainly capable of running his foundation while being chairman of Microsoft's board. His leaving now would be a big blow to Microsoft.
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