Companies like Microsoft and Shake Shack have recently experimented with the four-day workweek as part of an effort to help their employees achieve a better work-life balance.

And while cutting the business week by one day can motivate employees to get more work done in a shorter timeframe, there’s a downside that can come from only working four days per week. A shorter workweek could mean less time for opportunities that may advance an employee’s career in the long-run, like networking with important industry peers.

That’s according to Laura Vanderkam, a time-management expert who has written several books on the topics of productivity and work life-balance, including “Off the Clock: Feel Less Busy While Getting More Done.”

“People do the immediate stuff of their job that has to get done, but then you wind up shortchanging kind of the longer career-development stuff,” Vanderkam told Business Insider.

For example, a person working only four days per week may decide not to have lunch with a colleague or client that could have led to an important project in the future because he or she didn’t have expendable time to do so.

“I think there’s definitely arguments to put a cap on hours that have been inefficient before,” Vanderkam said. “I think there’s also a point where you cannot be more efficient without really losing some of the higher-value things that are important but not urgent.”

That’s not to say restructuring the workweek isn’t beneficial in some ways. There’s also a clear demand for work hours that are more manageable.

In a study of 7,500 employees last year, for example, a report from Gallup found that 23% of workers felt burned out always or very often, while 44% said they felt burned out sometimes at work. That could be making it difficult for employers to retain talent. Nearly half of the 614 human resources leaders surveyed by Kronos Incorporated and Future Workplace in 2017 said that burnout is the reason behind up to half of their yearly workforce turnover.

Cutting one day out of the workweek could help solve that problem while also potentially improving productivity by forcing workers to make the most out of their time in the office.

But according to Vanderkam, the answer is probably more about allowing for flexible hours than providing a blanket rule like reducing the workweek to four days. If an employee is struggling to work around important commitments unrelated to their profession, like doctor’s appointments or caring for a child or family member, he or she could request to work longer hours on Monday through Thursday and work a shorter day on Friday.  

“It’s going to be a question of optimization,” Vanderkam said of the ideal number of hours employees should work during the week. “And we don’t really know what the right number is. My guess is it’s not 80, my guess is it’s also not 20.” 

Originally published on Business Insider.

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