In the 2016 paper “Does Working From Home Work?” a team of economists looked at Ctrip, a 16,000-employee Chinese travel agency that had randomly assigned a small group of its call-center staff to work from home. At first, the experiment seemed like a win-win for workers and owners. Employees worked more, quit less, and said they were happier with their job. Meanwhile, the company saved more than $1,000 per employee on reduced office space. But when Ctrip rolled out this policy to the entire company, it caused a mess. One complaint swamped everything else: Loneliness.

Beyond lost creativity and companionship, the gravest threat to many companies from remote work is that it breaks the social bonds that are necessary to productive teamwork. Several years ago, Google conducted a research project on its most productive groups. The company found that the most important quality was “psychological safety”—a confidence that team members wouldn’t embarrass or punish individuals for speaking up.

But online communications can be a minefield for psychological safety, according to Bill Duane, a former Google engineer who now works remotely as a corporate consultant and researcher. “Whenever we read a sentence on Gchat or Slack that seems ambiguous or sarcastic to us, we default to thinking, You fucker!” Duane told me. “But if someone had said the same thing to your face, you might be laughing with them.”