There’s no simple explanation for why more women aren’t reaching top leadership positions in business, as Susan Chira explores in a thought-provoking piece for the New York Times. But one barrier seems particularly hard to get past: women in top positions often have to deal with the challenges that come with being one of the few, if not the only, women at their level.

Chira interviewed nearly two dozen women—some of whom reached the CEO level; others whose trajectories stopped short of the top spot—and found a common theme: not only is the push for more women CEOs moving at a “glacial pace” (a mere six percent of Fortune 500 companies have female CEOs, according to the NYT piece), but once there, women have to contend with issues of loneliness and dealing with a male-centric and sometimes less-than-welcoming work culture. (Chira wrote about a lot of different reasons why being in the top spot—or trying to get there—is tough, not just the ones mentioned below, and the full story is well worth the read.)

“Once you get to the top of the company, in most cases, you are dealing with a male kingdom,” Dina Dublon, who used to be chief financial officer of JPMorgan, told Chira. Jan Fields, who worked her way up from crew member at a McDonald’s restaurant to president of McDonald’s USA echoed this sentiment: “It’s very lonely. I was at a high level playing in a golf foursome with all high-level men. One said, ‘I didn’t know you knew how to play.’ I said, ‘You never asked me.’ I never drank with them. I never tried to be one of the guys. I spent more energy on performance.”

Fields was fired in 2013 after being “blamed for the first monthly drop in profits since 2003,” Chira writes. But businesses seeking a culprit for profit loss should think about the research that supports having women in executive positions: recent data from the Peterson Institute for International Economics found that companies with at least 30 percent of leadership roles filled by women added “6 percent to net profit margin,” Quartz reported.

A lack of women at the top hurts much more more than just profits. Research has shown that socially diverse groups (people of different backgrounds, race, sexual orientation, and of course, gender) think differently, and are “more innovative than homogeneous groups,” as this Scientific American article reported.

This is an important issue that will take serious effort to address and fix. In part, business leaders (and society at large) need to create ways to make the workplace more welcoming for people of all gender identities, which means taking a good hard look at how existing gender norms hinder everyone’s success.

It’s part of why Thrive Global has launched Redefining Masculinity, an editorial initiative dedicated to showing how harmful and antiquated “machismo-driven notions of masculinity imprison men in their careers and relationships and impact the workplace for women,” as Drake Baer writes on Thrive Global. While there’s a lot of work to be done, we can’t ignore the importance of examining gender roles as they function now in order to truly change the way we work and live.

Read more about the challenges that stand between women and the CEO position on the New York Times and read more about Redefining Masculinity on Thrive Global.