Because they want to see if they really like a girl or if they like someone else. But they don't realize how much the relationship means to the other person.
Why do boys cheat on girls?
I wouldn't make it sound like it's okay, but...hey, at some point in life all teenage boys to men, Cheat!! It's sad that it's, a "Man Thing" but I feel it shouldn't be done period!! The crazy part is women can cheat and are better at it too! Hahaha Just remember "Karma is a B****"