The one rule Mark Zuckerberg has for hiring new staff

Mark Zuckerberg has a simple test for new staff: he will only hire people that he would be willing to have as a boss.

The Facebook CEO made the admission on Wednesday evening at the Mobile World Congress in Barcelona, during a "town hall" style question and answer session.

I will only hire someone to work directly for me if I would work for that person. It's a pretty good test.

As for other HR tips? Zuckerberg said he believes in keeping teams "as small as possible".

"[Facebook] serves more than a billion people around the world but our team has fewer than 10,000 people. It's only possible because of modern technology. Big companies get bloated."

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