And to hear the 33-year-old entrepreneur tell it, he had to learn everything.
Now a titan of the tech industry and sitting at the helm of a company with a market capitalization of almost $550 billion, Zuckerberg says that when he launched Facebook, he had no idea what he was doing.
"I was 19 when I started Facebook, and I didn't know anything about building a company or global internet service," Zuckerberg says in a Facebook post published on Sunday.
"Over the years I've made almost every mistake you can imagine. I've made dozens of technical errors and bad deals. I've trusted the wrong people and I've put talented people in the wrong roles. I've missed important trends and I've been slow to others. I've launched product after product that failed," writes Zuckerberg of his missteps.
He also indicates he and Facebook still have room to grow.
"It's a moment to reflect on how far we've come from that dorm room at Harvard and how far we still have to go to bring the world closer together. And it's a moment to think about what we need to do better," Zuckerberg says.
"We are still early in this journey and we will keep working to improve. That focus has always been our strength, and that's what this year is all about."
Since the early days, Facebook has grown massively. Today, the social media behemoth sees 1.4 billion daily active users and 2.1 billion monthly active users. Notably however, in the most recent quarter, Facebook said users spent 50 million fewer hours per day on the platform. According to Facebook, that's due to algorithm changes made to reduce the number of viral videos displayed.
"The reason our community exists today is not because we avoided mistakes. It's because we believe what we're doing matters enough to keep trying to solve our greatest challenges — knowing full well that we'll fail again and again, but that it's the only way to make progress," he says.
Indeed, Facebook has had a challenging year. The social media conglomerate has come under intense scrutiny after Russian hackers disseminated "fake news" on the platform in a way that allegedly influenced the Presidential election. Further, the company itself has admitted that social media can be bad for users, if they scroll passively through content as opposed to engaging actively with individuals who mean something to the user.
In response to these and other challenges, Facebook has pledged to add 10,000 people to its ranks to — as of December 31, 2017, the social media giant had 25,105 employees — to address safety and security. Also, Facebook says it will change its algorithm to promote more local news and will prioritize news from "high-quality news sources" and users' friends.
"Bringing us closer together with our family and friends matters, and 14 years in I'm proud of what we do and grateful to be a part of something so meaningful," Zuckerberg says.
"It's an honor to be on this journey with you."
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