For serial entrepreneur Emma Grede, being "deeply ambitious" means working in-person five days per week.

Grede, a co-founder of apparel brands Skims and Good American, has an estimated $405 million net worth, according to Forbes — and her work ethic was shaped by working in the office everyday during her early career, she said on a May 12 podcast episode of "The Skinny Confidential Him and Her."

If you work at Good American, where Grede is the CEO, you're expected to be in the office every weekday, she added.

Grede, 42, "learned from proximity" when she was younger, she said. She sat near her boss in meetings, writing down "every phrase that would come out of her mouth," she said. When she had to make calls, she'd repeat what her boss said, learning from her word choice, cadence and presence.

"How are you learning if you're not, like, in it [and] on the job? We know some jobs need more proximity than others, but I'm in the product business ... If you're not in the room, you're not able to do that at an excellent level," said Grede, who was named a CNBC Changemaker on February 24.

In addition to her apparel brands, Grede is also a co-founder of cleaning product brand Safely and an occasional guest Shark on ABC's "Shark Tank."

"I have businesses that are relatively young and it requires people that come every day with 100%, put everything in and leave nothing on the table," she said. "I think I make it quite clear that if you're a three-day-a-week person, that's totally fine, it just doesn't work here. It doesn't work for me."

When circumstances require hybrid work, like a mom returning to her job after having a baby, Grede makes accommodations, she said.

"We want to create the conditions for ambitious people to be successful and that might mean, at certain points in their career, they need a different set-up," said Grede. "But ... for those starting out, for most people in the company, we have to be [in person] five days a week."

Many employees tout the benefits of hybrid work, according to 2023 Gallup data: 76% said they had improved work-life balance, 64% said they used their time more efficiently and 61% said they experienced less burnout or fatigue at work.

A minority of workers in the same data set noted a few downsides. Twenty-eight percent said they felt less connected to their organizations, 24% said they had decreased collaboration with their teams and 21% said they had impaired working relationships with their team members.

If you're a boss who struggles with the idea of remote work because you think your employees aren't as productive from home, you can offer them trainings to help them communicate more effectively online and get the most out of hybrid meetings, Lucid Software CEO Dave Grow told CNBC Make It on June 21, 2024.

The fact that "executives who are often the ones setting the policy still have a relatively high level of dissatisfaction is indicative that we have not gotten to the right end state" of hybrid workplaces, said Grow, whose company makes digital collaboration tools.

Of course, if your employees want to be in the office every weekday, there's little reason to stop them. "There's a lot of different ways that people come to work and there [are] always exceptions to every rule, because otherwise, you're not running a modern business," Grede said.

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