Mark Zuckerberg shares the best piece of advice Peter Thiel ever gave him

When Facebook (FB) was little more than an idea back in 2004 and valued at just $4.9 million, PayPal co-founder Peter Thiel put $500,000 into the social network.

The early investor cashed out big when the company went public in 2012 — the IPO raised $16 billion, making it one of the largest IPOs of all time — and turned Thiel's initial investment into over $1 billion.

In a recent interview, Y Combinator asked Facebook founder and CEO Mark Zuckerberg about the best advice Thiel ever gave him.

Zuckerberg said of the self-made billionaire: "Peter was the person who told me this really pithy quote: 'In a world that's changing so quickly, the biggest risk you can take is not taking any risk.' I really think that that's true."

When it comes to decision-making or shifting direction within your company, there's inevitably going to be a level of risk involved.

"People are going to point to the downside risks of that decision. And locally, they may be right," Zuckerberg said. "For any given decision that you're going to make, there's upside and downside. But in aggregate, if you are stagnant and you don't make those changes, then I think you're guaranteed to fail and not catch up."

While you can't be afraid to introduce new ideas and innovate in order to stay ahead of the curve, Zuckerberg cautioned against making dramatic changes, since if you're doing stuff well, big moves may not be necessary.

"As CEO, it's your job to not get into a position where you need to be doing these crazy things. I think when stuff is working well, you're learning incrementally and growing that way," said Zuckerberg. "You want to actually evolve in a way where you're working with your community and taking steps and learning."

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