Elon Musk’s net worth once again topped the $1 trillion mark this week—and few people have had a closer look at the forces behind his success than his former deputy Linda Yaccarino.

The 30-year media veteran was tapped as CEO of then-Twitter in 2023, stepping in as Musk was remaking the social platform from the ground up, and she got a firsthand look at the philosophy driving his companies, from Tesla to SpaceX: Move fast, rethink everything, and don’t wait for tomorrow.

“The reason his companies are singular in what they deliver is because of the insatiable sense of urgency. There’s not a deadline for a project or to ship something, a product—it’s now,” Yaccarino told Fortune. 

That mindset, she said, changes how you approach virtually any challenge. Rather than simply working toward a deadline, it forces you to strip a project down to its most essential pieces and figure out what actually needs to happen to succeed.

“A lot of people talk about first principles, but that’s what it forces you to do,” Yaccarino added.

And she saw it almost immediately. When she arrived, Twitter was in the middle of another round of upheaval, including the retirement of its blue-bird logo and, eventually, its transformation into “X”—all with a fraction of its pre-Musk staff. Misinformation, hate speech, and bots also became growing concerns, issues that have continued to follow X since her 2025 departure.

For Yaccarino, though, the flux was part of the appeal. For all the challenges that came with running X and working for Musk, she said the hardest moments in a career can ultimately be “like a gift.”

Before working with the world’s richest man, Yaccarino’s career began with a clerical error

That belief in leaning into difficulty began taking shape long before Yaccarino ever worked for Musk.

Yaccarino grew up on Long Island to an Italian-American family, and she and her two sisters were raised with what she calls an “immigrant mentality”: Work hard, rely on yourself, and remember that family matters regardless of professional success or failure.

That confidence was tested early in her career while as a telecommunications student at Penn State University. Yaccarino landed an internship at NBC for the summer before her senior year. But when she showed up at 30 Rock for her first day, the company had no idea who she was.

“They had literally no record of me,” Yaccarino recalled. “So, soul crushing to say the least.”

She went home that night feeling like she had failed. But the setback quickly became a footnote. NBC asked her to return the next day, placing her in the sales department, and marking the start of a three-decade career in media.

“That’s where the love affair happened,” Yaccarino said. “I got to be amongst the ranks of people that were leading industry and inspirational in pop culture, newsmakers of the headlines. And who couldn’t become a fan and a disciple of the industry at that time?”

After graduating in 1985, Yaccarino gradually climbed the ranks in media sales and advertising at Turner and NBCUniversal. In 2020, she was named chairman of global advertising and partnerships at NBC, where she helped notably lead the company’s early advertising strategy for the 2028 Los Angeles Olympics. In total, she was overseeing some $13 billion in annual ad revenue.

But when Musk asked her to make the jump to tech, Yaccarino said it was hard to pass up: She saw him as “singular in his ability to transform human conversation and movement,” and being part of that mission at Twitter/X was “consequentially important” at the time.

Yaccarino’s advice for Gen Z: ‘Go to the uncomfortable’

After two turbulent years at the helm of X, Yaccarino resigned from the social platform in July 2025 and began thinking about where to take her career next. She said she had plenty of options but wanted a path that would challenge her again, so she sought advice from her mentor, billionaire financier Michael Milken, who now chairs the Milken Institute.

“He said, Linda, ‘You have so many paths to take, and they’re all good paths. So you’re not going to make a mistake, but don’t choose a good path,’” she recalled. “‘Choose another consequential one. You spent so much time doing world-changing types of things at X. Be consequential again.”

That advice led Yaccarino to becoming the CEO of eMed, a $2 billion healthcare startup focused on telehealth and GLP-1 treatments, backed by investors including Tom Brady.

It’s also a lesson she encourages Gen Z to carry into an increasingly AI-driven workplace: Don’t simply get better at what everyone else is doing. Find the skills and experiences that make you stand out.

“Celebrate those skills that you have that are at the intersection of art and science, or magic and math—not just what the screen tools give you,” Yaccarino said, adding that human skills like empathy and decision-making are also critical.

Above all, she encourages people to run toward problems. Otherwise, she said, their careers could be “kind of boring”—something her own career, thanks in part to Musk, has been far from.

“Comfort is complacency—that’s not going to make you consequential in your career or your life,” Yaccarino said. “So, go to the uncomfortable.”

This story was originally featured on Fortune.com