When Facebook CEO Mark Zuckerberg went to Hawaii late last year while on paternity leave, photographers for the Daily Mail went into full paparazzi mode to capture the billionaire’s trip to a local burger joint.
There were pics of Mark Zuckerberg with a training toilet for his daughter. Mark Zuckerberg with a backpack. Mark Zuckerberg smiling, holding shave ice. In many of the photos, Zuckerberg was seen walking with a man the publication identified only as “a male friend.”
“It was like, here’s Mark Zuckerberg and some other guy, noted only for the fact that he’s wearing Crocs in public,” laughed Chris Cox, Facebook’s chief product officer and, as he was described, a close friend of Zuckerberg’s. “The only time in my life I’ve ever worn Crocs in public was that day.”
Most people outside of Facebook and its close observers probably wouldn’t recognize Cox, but the 35-year-old is Facebook’s most important product executive, an unofficial title that was reconfirmed this week when he was put in charge of all of Facebook’s apps — Facebook, WhatsApp, Instagram and Messenger — a lineup that reaches billions of people monthly and generates most of Facebook’s $40 billion in annual advertising revenue.
But while Cox is very much behind the scenes compared to Facebook’s celebrity bosses, Zuckerberg and COO Sheryl Sandberg, internally he’s seen in the same notoriety.
Cox represents a key aspect to the company’s culture: Loyalty. He has been at the social giant for more than 12 years and is a trusted adviser to Zuckerberg. Arguably, Cox has become Zuckerberg’s most essential executive.
He runs the new hire orientation every other week, welcoming all new employees to the company. He’s a frequent speaker at Facebook’s Friday all-hands meetings, and he has been running Facebook’s core product for almost a decade. He is also one of Zuckerberg’s closest friends — they live near each other in Palo Alto and their wives are also close — a significant detail at a company that’s been through the kind of drama Facebook has seen over the past 18 months. That friendship makes it easier to navigate the kinds of tough scenarios Facebook keeps finding itself in.
“When you know someone really well, you know how to talk to them. You know who they are, and you know how to listen to them,” Cox said. “All of that stuff just makes getting work done together a lot easier because so much of working with somebody is communicating what you care about and why. Knowing somebody well means you [don’t] have to get to the bottom of what someone’s motivations are every time you interact.”
Cox joined Facebook in 2005 as a product engineer and helped build early versions of Facebook’s News Feed. He also ran human resources for a short time — hence why he’s still pegged as the Facebook executive who welcomes the new hires — and quickly became a key figure internally as the company grew. He’s been running product for Facebook’s flagship app for most of the past decade but has taken on other roles and responsibilities along the way, with stints running the growth team, overseeing Oculus and helping to launch Facebook’s enterprise product, Workplace.
“A lot of my closest friends are here,” Cox said. “It’s a big part of my life. I feel lucky I stumbled in here back in 2005. I was completely randomly lucky to be in the right place at the right time on that one.”
Now Cox has his most important role yet, overseeing Facebook, Instagram, Messenger and WhatsApp at a time when Facebook is under more scrutiny than ever to get things right. Cox declined to comment on the leadership shuffle in his interview with Recode.
After a significant tenure at Facebook in ever-more-important roles, Cox has had plenty of opportunities to do something outside the social network, but he has always chosen to remain. The impact you can have at Facebook is hard to replicate anywhere else, he says.
“The first hour of my week every week is ‘hey, this is serious,’” Cox said, referring to the message he gives employees during new hire orientation. “‘You have an opportunity to make a big impact here. We all need to pay very careful attention to that.’”
Facebook’s reorganization comes on the heels of the company’s biggest scandal to date, where it was learned that an outside research firm, Cambridge Analytica, obtained Facebook users’ data without their consent. It prompted the U.S. Congress to call Zuckerberg to D.C. to testify. He performed well, but the moment shook the company.
Elevating Cox helps clear the decks a bit for Zuckerberg, whose role as company ambassador is getting bigger and bigger. His Congressional testimony revealed how many people still don’t understand how the company works or what its products do — and don’t do. Zuckerberg has increasingly been the outward-facing leader of the company, and he announced in January that his goal for this year was to fix Facebook. That’s easier to do when someone else is helping manage your core group of products.
Cox, certainly, will be key to making that fix work.
“I just think it’s important work,” Cox said. “It’s that simple.”
This article originally appeared on Recode.net.