1) Thinking that because you're young, you should not commit/get serious.
2) Thinking that because you're in a relationship, you won't be able to "work on yourself".
3) Thinking that because you have had bad experiences with ex's, you should either be a player or never trust a partner again.
4) Thinking that you should not get attached/fall in love.
5) Thinking that you should not clearly express your feelings (especially in early stages of a relationship).
6) Thinking that you have to take things slow. (Go at whatever pace you want and feel in your heart is best, seriously)
7) Thinking that you look clingy/creepy if you talk a lot and want to spend a lot of time together (this is actually a good thing ps)
8) Thinking that you have to play hard to get. (If the other person is mature, they will just get fed up with your BS and move on, and I would 100% advise them to do so.)
9) Always "wanting what you can't have"..........................
10) Thinking that if you love the person, you should ignore your gut feelings, like these ones for example.
Just grow up people. These trends do not make you look "cool" in anyway, nor do they make you look like a mature, intelligent human being. Stop thinking these ways, you will have a much more successful, and most importantly, HAPPY love life if you listen and FOLLOW your heart, no matter what your age or gender.