Why We Can't Predict Who We'll Fall For

Have you ever found yourself falling for someone surprising? Someone who didn't have the characteristics you thought you were looking for in an ideal mate? Recent research shows that relationship experts are unable to predict who will like whom, even when prospective daters have completed more than 100 surveys describing themselves and their mate preferences. Joel et al. (2017) used machine learning to try to predict who would particularly like whom at speed-dating events; however, the researchers were unable to predict the “spark" or unique attraction which sometimes occurs between two people. But we must know ourselves better than researchers can ever know us, and I’m sure that most of my friends would agree that they could do a better job than researchers at predicting who they would choose as partners for themselves. Therefore, it may be surprising to learn that we don’t do a very good job ourselves of predicting whom we will like and why. There are good reasons that we are not so good at predicting who we will fall for.

Unconscious Preferences

When we try to predict whom we might like to date or whom we might find to be an ideal partner, we are relying on conscious thought and deliberation. However, many of our preferences for an ideal partner are unconscious. For example, when we consciously state our preferences for an ideal long-term partner, most of us say that traits such as kindness, mutual affection, or intelligence are more important than physical attractiveness (Buss et al., 2001). And although both gay and straight men are more likely to say that physical attractiveness is more important to them than lesbian and straight women are (Lippa, 2007), experimental and speed-dating studies consistently show that physical attractiveness is equally important to both men and women (Eastwick and Finkel, 2008; Fugère et al., 2017; Sprecher, 1989)—and that physical attractiveness has a stronger impact on our dating decisions than factors such as personality or education (Luo and Zhang, 2009). The preference for a physically attractive ideal partner may be unconscious. Eastwick et al. (2011a) found that when assessing unconscious preferences using a reaction time task, both men and women equally preferred an attractive partner as an ideal mate.

Furthermore, our unconscious preferences may change over time, especially for women. Heterosexual women prefer more masculine-looking men, and more symmetrical men, when they are in the most fertile portion of their menstrual cycle (Roney and Simmons, 2008; Thornhill and Gangestad, 1999). Also, when women’s estrogen levels are high, they are more interested in men other than their primary partners; however, when their progesterone levels are high, they are more interested in their primary partners (Grebe et al., 2016). 

Concern for Others

It is also surprising to learn that we are very willing to date partners who are decidedly less than ideal. Joel et al. (2014) asked heterosexual men and women to list traits that would be “deal-breakers” to them when considering a potential partner. Individuals tended to list traits such as opposing religious or political views, smoking, and sexual unfaithfulness as deal-breakers. However, when the participants were told that another individual participating in the study with three of their deal-breaker traits wanted to date them, a full 74% of these individuals agreed to exchange contact information with this “unacceptable” potential partner. The researchers contrasted this result with a hypothetical condition in which participants thought they would agree to date an undesirable partner about 46% of the time, which is still an astonishingly high percentage. The researchers believe that we are unwilling to reject others whom we consider unsuitable partners due to concerns over hurting their feelings.

The Spark 

Although we all have our own ideas about the traits our ideal partners should have, what seems to really matter to our dating future are our in-person interactions. When we feel a spark when interacting with a potential date, our preferences and deal-breakers may not matter at all. Researchers created fake profiles matching each participant’s most desired or least desired traits for an accomplice. Then the accomplice met the participant in person and delivered standardized, scripted remarks. Eastwick et al. (2011b) found that after meeting in person, the participants' trait preferences appeared to have no influence at all on their liking for the accomplice. This research suggests that even traits which we consider to be essential (or essential to avoid) in a mate may not matter much after feeling a spark during an in-person interaction. This research also helps to explain why trait profiles on online dating sites are not very useful in determining whether we will actually like a potential partner (Finkel et al., 2012).

Fall for Someone Unexpected

Given that we have a tendency to date people who don’t match our own preferences, you might think that our future relationships wouldn’t work out very well. However, our preferences are malleable, and most often we have the good sense to change them. We tend to downgrade the importance of our previously preferred traits if our current mates do not possess them—and to upgrade the importance of the positive traits our current partners do possess (Fletcher et al., 2000). We also tend to idealize our current romantic partners and therefore we may believe that our mates possess positive personality characteristics that even our partners don’t believe they possess themselves (Morry et al., 2010). Also, regardless of the traits our mates do and don’t possess, the more we get to know, like, and respect each other more, the more our attraction naturally grows and deepens (Kniffin and Wilson, 2004). So, go ahead and fall for someone unexpected. You may be surprised at how well your relationship progresses.

About the Author

Madeleine A. Fugère, Ph.D., is a professor of Social Psychology at Eastern Connecticut State University, and her areas of expertise include attraction and romantic relationships.