Juggling multiple roles at work can kill your performance.

Many employees wear multiple hats today, whether they’re handling very different brands, or they’re serving as both supervisor and staffer.

But a new study suggests that workers who feel like their multiple identities conflict with each other perform worse than those who embrace playing multiple parts.

Ohio State University researchers took 763 employees at a customer service call center where workers represented very different credit cards. Each one had to try selling additional products and services to customers on calls, so the research team looked into whether this identity crisis helped or hindered sales.

It’s all a matter of perspective. The study authors asked the employees whether life would be easier if they represented only one brand, or if handling conflicting clients actually made them better sales reps for both. And the workers who felt most conflicted about representing different brands had lower-than-average sales for the four months after they took the survey. But the ones who believed juggling contrasting brands actually enhanced their work with each one had better-than-average sales.

Also interesting: The more someone working the phones took on the customer’s point of view, the worse their sales were. They struggled to reconcile their identity as a seller with that as a buyer, the way a supervisor who is too empathetic with employees can be a less effective manager.

Study coauthor Steffanie Wilk suggested that companies help employees find the common elements between their different identities to help them resolve these internal conflicts. The different credit cards offer a similar rewards program that all customers can benefit from, for example. Or someone in middle management, wearing the hat of both a boss and an employee, can be reminded that the whole company is working toward a common goal.

“If your employees feel they have to make trade-offs between different role identities in the workplace, they may not do as good a job,” Wilk warned in her report. “There needs to be connections between the identities that make sense to your employees. If there is conflict, your employees will ruminate, take up their mental energy, and struggle with their jobs. But if the connections are there, it can help.”