April 30, 2014 -- Some people worry about their jobs, bank accounts or whether they're married with kids before they turn 30.
When you're billionaire founder Mark Zuckerberg, you can dig a little deeper.
Zuckerberg mentioned his upcoming May 14 birthday today at Facebook's F8 Developer's Conference in San Francisco -- and revealed a mature new motto he said he hopes to implement at the social networking company.
"My goal is to build a culture of loving the people we serve," Zuckerberg said.
Zuckerberg hasn't always been such a zen master. Here's a look back at a few of his bolder moments that show how the tao of Zuckerberg seems to have shifted over the years.
The Old Motto
Facebook's old guiding principle wasn't as mellow as the new one a mature Zuck shared today.
"We have a saying: 'Move fast and break things.' The idea is that if you never break anything, you’re probably not moving fast enough," the wrote in a letter to investors before the company went public in 2012.
In February, Zuckerberg celebrated Facebook's 10-year anniversary and reflected on the journey in an open letter that made some critics question if he had a Messiah complex.
"When I reflect on the last 10 years, one question I ask myself is: why were we the ones to build this? We were just students. We had way fewer resources than big companies. If they had focused on this problem, they could have done it," he wrote at the time.
"The only answer I can think of is: we just cared more."
Squeezing Joy Out of the Haters
Months after a lackluster IPO, Zuckerberg said he found a way to leverage the attention of critics as a positive.
"This is a perverse thing, personally, but I would rather be in the cycle where people are underestimating us," he said, according to Forbes. "It gives us latitude to go out and make big bets that excite and amaze people."