A new study from the University of Iowa suggests that businesses who hire extroverts may not be getting the gregarious, helpful team players they think they’re hiring.

“The traditional thinking is that people with an extroverted nature help other people, but what we found is that what triggers that nature is important,” says Ning Li, assistant professor of management and organizations in the Tippie College of Business. “We found that receiving a reward is what activates that nature.”

Because of that traditional thinking, employers often hire more extroverted people for jobs, especially those that require lots of interpersonal exchanges, thinking that they are more apt to be team players. But Li said his research suggests that is mainly true for extroverted employees who are motivated by impression management—that is, they want to project a good image.

Those extroverts who are not motivated by impression management are less likely to help others.

“If impression management motives are muted, extroverts will be less likely to channel their need for social attention directly toward citizenship behaviors,” Li says. “Rather, extroverts who are less concerned with their image may be less inclined to engage in altruistic actions such as helping others, yet still draw social attention.”

Li’s study involved professional workers in China, who were taking part-time MBA classes at a Shanghai business school. The students were given a test that teased out their motivations, and their workplace supervisors were asked to assess their overall workplace citizenship.

The results found that extroverts who scored high on impression management were more likely to receive positive reviews from their supervisors as good workplace citizens. Those extroverts who scored low on impression management also scored lower on their supervisors’ citizenship scores.

The researchers followed up the Shanghai study with a laboratory test in the United States, where college students were asked to go above and beyond the minimal tasks required in a project and help other workers. There was no additional reward offered for doing the extra work.

Li’s team found that extroverts who were interested in projecting a positive image were more likely to perform the additional work than those who were not interested in looking good to others. Li says these findings show that extroversion by itself is not a guarantee that a worker will be a good, helpful team player.

He says the study results suggest that employers look beyond an employee’s personality and find out what triggers their extroversion.

"Extroverted employees who are motivated by impression management motivation can be relied upon when interpersonal helping is necessary," Li says. “If managers know subordinates' personality profile, they are also at an advantage if they can glean these employees' motivations to project a certain image."

But Li said that compared to most introverts, who mostly just want to be left alone, even those extroverts who are not interested in projecting a positive image are still more helpful.

Li’s study, “Getting along to get ahead: The effect of extroversion on interpersonal citizenship when impression management motives are high,” was co-authored with Dan Chiaburu, Adam Stoverink and Xin-an Zhang. It will be published in a forthcoming issue of the Journal of Management.