Few are eager to be the person at the office who points out a problem, for fear of being labeled disruptive or negative. And much has been written on the importance of positive attitudes such as hope and optimism at work. Well, a new study indicates that complaints—and even anger—can actually improve outcomes in the workplace.

A series of studies highlighted in Human Relations journal (pdf) suggest that expressing anger in the workplace can actually lead to more people acknowledging a problem and getting it fixed. One study the authors highlighted found that negative emotional events in the workplace had a positive outcome 70% of the time. This doesn’t mean it’s bad to express positive feelings at work—those led to positive outcomes 94% of the time—it just means that a negative emotion doesn’t always lead to a negative outcome.

When a manager sets a “negative affective tone”—basically, when they convey dissatisfaction—employees in both individual and team settings tended to perform better. The findings aren’t universal; in the study on individual settings, employees who were “agreeable” performed better in response to negative emotions than those who were not as agreeable. (So if you’re a nice person, you’re more likely to respond well to anger.) In teams, the manager’s negative tone encouraged workers not to settle for less, and to delve into deeper problems.

The paper is a response to the feel-good studies that focus on what’s called “symmetrical outcomes”—the idea that positive emotions are mostly good for employees, and negative emotions lead to discontent. The authors, Dirk Lindebaum and Peter Jordan, argue that researchers should also look at the long-term utility of an emotion, and at the effect on the person on the receiving end.

There are similar observations in social situations, going against the idea that positivity is always the best policy. For example, sadness after a loss can lead to more open social connections. And even laudable qualities such as compassion can lead to fatigue and emotional burnout.

It’s worth noting that the researchers don’t instruct employers or employees to be unkind. So when it comes to expressing anger about something at work, you should probably still be polite.