When it comes to flexibility in the workplace, with great power comes great responsibility.

Debates over unlimited vacation policies and extended family leave have been going on for years. However, a crucial question has been largely ignored: whether these seemingly free-wheeling policies have unintended consequences?

Unlike companies that set their vacation days, those with unlimited vacation policies ask the employee to make that judgment. And that's what could backfire in workplaces. When employees who feel that they lack power (like women and minorities) are given that responsibility, it actually serves to disproportionately pressure them to work more.

'Always On'

So-called 'guilt-based management policies', like unlimited vacation and discretionary family leave or remote working, provide flexibility for employees to explore work/life balance. But that also means each worker must determine how much is too much within the context of their individual work situation.

Since no company truly means 'unlimited,' every vacation is a complex navigation of internal politics, Jonathan Nightingale, chief product officer of product discovery website Hubba, writes on Medium. Taking time off likely means inconveniencing co-workers in some way, which can be even more difficult for women and minorities--or any employee who is "not a part of the in-group," as Nightingale writes.

For those who are hesitant to take time off, it might seem easier to commit to being available and "always on," when out of the office. "That leads to martyrdom, burnout, and turnover," Nightingale writes. "It can poison a culture."

And when it comes to family leave or working from home, research suggests that men benefit more than women from these policies. While gender-neutral family leave policies are meant to reduce stigma, a Public Radio International study of economics professors found that men who took advantage of gender-neutral family leave policies experienced increased productivity, while women suffered a loss (not surprisingly, since women's time off was dominated by the physical effects of giving birth). While PRI only studied a specific subset of the working population, the logic would seem to hold up across occupations.

Co-workers' perception of remote workers plays into this complicated issue as well, says Stefanie Johnson, a professor of management at the University of Colorado, Boulder's Leeds School of Business. "Family friendly policies are only useful for women if your culture is accepting of it. If a woman is working at home, people might think she's slacking off and spending time with her kids, but if a man stays home, people think he's staying out of the office to be more productive."

A Work in Progress

To counter these misconceptions, Hubspot, which has offered flex schedules and unlimited vacation for nearly 10 years, provides managers with training to help with the "spiritual, softer side of management," says chief people officer Jim O'Neil. Since no one formally tracks time in and out of the office, it's the manager's responsibility to pay attention to social cues, make sure people are taking enough time off and that the team's culture is supportive.

"A lot of it is around sensitivity about how every person has a different situation and making sure you're helping people succeed in their unique situation," says O'Neil. "A lot are first-time managers and maybe haven't experienced different life stages yet."

Perhaps due to all these internal politics, flexible benefit plans don't actually make employees feel better about the company in the long run, says Carol Watson, senior director of global member engagement at New York City-based Diversity Best Practices. Her company typically works with mid- to large-sized companies like Unilever to find solutions for cultural change.

Evans says there hasn't been a lot of research on the effects of unlimited paid vacation policies on workplace morale yet. That's because, despite their popularity in the media, a tiny subset of companies offer it. (Only one percent of U.S. employers, according to data from Virginia-based HR professional group, the Society for Human Resource Management.)