Men are known to overestimate how sexually appealing they are to women they’ve only just met. You’d think, though, that they’d be better at gauging the sexual desires of their own partners. Think again. A new study published online in the Journal of Personality and Social Psychology has found that men in long-term relationships tend to underestimate their partner’s sexual desire for them. However, according to the researchers, this miscalculation isn’t always a bad thing.

For the study conducted by researchers from various Canadian institutions, the team recruited 48 heterosexual couples between ages 23 and 61 from the Greater Toronto Area. Most of the couples were married, and those who were not cohabitated. The couples were asked to complete a 10-minute survey each night for 21 consecutive days indicating their own sexual desire and what they perceived to be their partner’s sexual desire for them. In addition, the participants were asked to report their own sexual satisfaction and sexual frequency in their relationship.

Results showed that men typically underestimated how sexually interested their partners were.

“We had predicted the underperception bias in established relationships,” lead researcher Dr. Amy Muise told Medical Daily. “But it is certainly interesting how context (initial encounters versus established relationships) changes the direction of perceptual biases about sexual desire.”

While at first this underestimation of a partner’s sexual desire may seem detrimental to a couple’s sex life, the study suggested that it may serve a purpose. For example, men who mistook their partner's sex drive likely had wives and girlfriends who felt more satisfied and committed to their relationship overall.

“Theory would suggest that underperception might serve the function of keeping people motivated to entice their partner's interest and avoid becoming complacent,” explained Muise. “Specifically the sexual underperception bias may help manage the careful balance between pursuing sexual connection with a partner and avoiding sexual rejection.”

In addition, the men seemed to project their own sexual desires on their partners by assuming that when they felt strong sexual desire their partners felt the same. On the other hand, the men tended to underestimate their partner’s desires on days when they were less sexually motivated.

According to Muise, her research helps highlight how important it can be to communicate sexual desires with your partner.

“When people were accurate in their perceptions of their partner's HIGH desire, both partners felt more satisfied and committed to the relationship,” said Muise, explaining that while indicating that you are in the mood to your partner may not always lead to sex, it may help to boost overall relationship satisfaction.

Other research has also shown how sexual perception often changes once we are in a relationship. One study showed that although women typically prefer not to be sexually objectified, feeling desired within a long-term relationship can go far toward relationship satisfaction. However, the researchers were quick to emphasize that this finding did not extend to all women.

Source: Muise A, Stanton SCE, Kim JJ, Impett EA. Not in the mood? Men under- (not over-) perceive their partner’s sexual desire in established intimate relationships. Journal of Personality and Social Psychology . 2016