Playing hard to get might be a good way to temporarily hook someone who is uncomfortable with intimacy — if that’s what you’re looking for. The myth that we should play it cool has kept many a potential relationship from being born. Most of us err on the side of believing we have to play it cool. The truth is, if you’re too good at playing it cool, that’s probably the sign of a problem. And if you’re not skilled in this art, you’ll probably “white-knuckle” your desire until you can’t hold it in any longer, and then let it all out at the moment you’d least want to. (How many times has this happened to me?)
No, the research is quite clear on this: showing someone you’re interested is one of the best ways to spark attraction. Eli Finkel, a professor of psychology at Northwestern University, used speed-dating events as a vehicle to study romantic attraction. His research showed that playing hard to get is not the way to go. A key to sparking romantic attraction is to show someone that you’re interested in him in particular, not because of a generalized sense of need on your part. For example, Finkel suggests that you might convey the message “You are awesome, and I am so excited that I get to have this time with you” while also conveying the message “I have been around the block — and you’re the one that really interests me.” So, don’t hold back, let the next person you like know it — it’s an intimate and effective way to spark a new connection.
— Ken Page, Deeper Dating, p. 134