Bill Gates is one of, if not, the biggest names in computer science, a dedicated philanthropist responsible for saving millions of lives, and the second richest man in the world – just behind Jeff Bezos. So, what could he possibly regret?

Apparently, letting Google launch Android.

The ex-CEO of Microsoft spilled the beans on this particular qualm at a “Lessons from Luminaries” event held by Village Global, a venture capitalist organization, in San Francisco.

“In the software world, particularly for platforms, these are winner-take-all markets,” Gates said, adding, “So the greatest mistake ever is whatever mismanagement I engaged in that caused Microsoft not to be what Android is.”

He went on to say Android is the standard non-Apple phone platform, making it a natural asset for Microsoft to win.

“It really is winner takes all,” Gates told the audience.

“There’s room for exactly one non-Apple operating system and what’s that worth? $400 billion that would be transferred from company G [Google] to company M [Microsoft].”

Village Global/YouTube

Allowing Google to acquire Android was not his only mistake, it seems. Gates also admitted regretting some of the sacrifices he made in terms of his work/life balance.

When it comes to starting a business or project as Gates did with Microsoft, he says he has “a fairly hardcore view that there should be a very large sacrifice made during those early years.”

But he preceded that statement with the idea that “you can over worship and mythologize the idea of working extremely hard,” conceding that it is true he didn’t believe in weekends or vacations when he was younger.

“I don’t recommend it,” he deadpanned. “I don’t think most people would enjoy it.”

“Once I got to my 30s, I could hardly even imagine I had done that because by then, some natural behavior had kicked in and I loved weekends and my girlfriend liked vacations and that turned out to be kind of a neat thing.”

So, there you have it. Those are some of his biggest regrets.

As for some of his biggest achievements? Earlier this year, Gates revealed what he thinks are the “best investments [the Bill and Melinda Gates Foundation] has ever made” in a piece for the Wall Street Journal. He said donating money to companies responsible for purchasing and distributing medicines have really paid off.

And just in case you are wondering, Gates does now use an Android phone. He is also privy to taking “lots” of vacations. “My 20-year-old self is so disgusted with my current self,” he said.

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