On Monday, CEO Dara Khosrowshahi wrote an “un-Uber-like” open letter asking Londoners to forgive mistakes it made in an effort to win back the right to operate in the city.

That same day, Arianna Huffington spoke at the Fortune and Time CEO Initiative conference in New York City about a number of other ways in which the company has evolved.

“If you were a top performer delivering growth, a lot was forgiven you,” the Thrive Global founder and Uber board member said, describing what Uber’s business culture was like before a blog post by a former employee Susan Fowler sparked one of the most significant changes within a company in recent history, including the resignation of its CEO Travis Kalanick.

Fowler’s blog post published in February 2017 reflected “on one very, very strange year at Uber”—an experience that included accusations of sexual harassment and accounts of mismanagement and other bad behavior. It prompted Kalanick to hire former U.S. Attorney General Eric Holder to investigate the claims.

Huffington, the only woman on the board at the time, got involved from the beginning and chaired the subcommittee that oversaw the Holder investigation. During a “raw and emotional” all-hands staff meeting just two days after Fowler’s post, Huffington said she made a number of pronouncements to reassure Uber’s then-14,000 employees that change would be coming.

“I named top performers who misbehaved ‘brilliant jerks,'” Huffington told Nancy Gibbs, editorial director of Time Inc. News Group, while on stage. “And I announced at that all-hands that Uber would become a place of zero tolerance for brilliant jerks.”

The actions that followed that all-hands, including the dismissal of 26 employees after the results of Holder’s investigation were announced, sent a very clear message “that we meant business” and were serious about making fundamental changes.

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Change is critical—even if it means losing top performers—because the world has changed and what happens in the culture of a company affects business metrics, said Huffington, who founded media website HuffPost.

Uber’s 65 million users love the product. Now, Uber is on a journey to become a company they will love too, she said.

Here are a few ways Uber is changing:

1. Surface Problems Quickly

“Surfacing problems faster is now a key element of a thriving culture,” Huffington said. “I see culture as becoming the immune system of the company.”

Healthy companies have processes in place that allow employees to share problems and the proper training for managers to handle those issues quickly.

“One of the problems we had was that 62% of Uber managers had never managed before,” she said. “They didn’t have the skill set required to manage.”

2. Changing the Myth About Success

“We are suffering from this delusion, both at the individual and corporate level that in order to succeed we need to burn out,” Huffington said, adding that modern science and research shows this is untrue.

Instead, people need to find ways to recharge either through sleep, hobbies, or even turning off their smartphones. Thrive Global works with companies to like Airbnb and Accenture, to produce cultures where employees are not burned out. The startup also has a consumer-facing website that publishes articles on wellness and healthy living.

“At Uber, you can see the connection between burnt out people acting out,” Huffington said. “I know that when I’m tired I’m more reactive, I’m less empathic, I’m not as creative. We can all remember how we operate when we’re running on empty. When you’re a 26-year-old engineer or manager you may do worse than being reactive and not being emphatic, and that acting out is at a very high cost to the business.”

3. Changing What Uber Values

Uber has changed or even eliminated a few of its values in its effort to change the culture. One of the first things to go was a cultural value of “always being on,” Huffington said. “Being always on is not the way human beings operate at their best,” she said.

Another one was striking “longer” from its “work smarter, harder, longer” cultural value because working smarter and longer contradict each other.

Finally, Uber renamed its war room, to the peace room because “symbols matter,” she said.