9 scientific reasons you suck at kissing (both guy and girl edition)

According to The Science of Kissing: What Our Lips Are Telling Us, 59 percent of men and 66 percent of women have ended a relationship because their partner was a bad kisser.

Dudes: No one wants to make out with you because...

1. Your tongue is MUCH too aggressive.

According to The Art of Kissing, this was women’s most frequent complaint about their make-out partner. You're kissing, not swabbing for strep throat. Reel it in, fellas.

2. You're not coming up for air.

People tend to enjoy kissing more when they're not being suffocated. A good makeout sesh happens in waves...intense--calm--intense--calm...so that everyone can keep sucking oxygen as well as face.

3. You're not "listening."

"Match your partner's tempo. Reply to their tongue action with similar tongue action. Leading and being aggressive can be good but being oblivious is bad," explains The Art of Kissing.

4. You've got too much facial hair.

53% of women interviewed for The Art of Kissing said they prefer (to kiss) a clean-shaven man.

5. You're ONLY kissing her on the mouth.

“Women's favorite spot to be kissed, other than the mouth, is the neck," explains kissing expert William Cane. Ninety-six percent of women he interviewed reported that they like neck kisses.

6. You're a one-trick pony.

“Women also complain that men don’t do enough variations in kissing, that they’re too machine-like or repetitive," Cane said. "Women would like a number of different kisses: the neck, the ears, “liposuction,” which is moving from the upper lip to the lower lip…be creative.”

Ladies: No one wants to make out with you because...

7. Your lips are locked tighter than Fort Knox.

Research shows men prefer wetter kisses with more tongue action. So open up, Ladies.

8. You always wait for him to kiss you first.

Even when you've been with someone for a while, initiating a kiss is a leap of faith. And contrary to popular belief, guys don't always like to be the ones taking it.

9. You're kissing him on the neck.

While almost 100% of women interview for The Art of Kissing said they LOVED neck kisses, only 10% of men said they liked to be smooched there. So keep it above the chin, ladies.

OK, now you've got all the science you need to be an A+ make out partner. Go out there and make us proud.