He's too...nice. (The "Bad Boy" syndrome)

And the award for the best side smirk in the year infinity goes to Ian Somerhalder

As much as you ladies would like to deny it, you like a "bad boy".

 It's factual. You like a challenge, a bit of a project to work on, you want to spend your time taming this wild beast so you can finally bring him home to Mummy and Daddy. What you don't realise is you are not an expert animal trainer and you will get scarred in the process, your thirst for a bad boy that will only be good for you can lead to tears when you discover that you can not change a guy. Don't get me wrong a guy can change for you but 99.9% of the time, he came to this realisation by himself, something has finally clicked into place for him and what you already knew, he's only just realising.

Now it is perfectly okay to want this tough, strong, borderline dangerous bad boy who for some reason has a weakness for you however, what make the nice, sweet, admirable good guy so undesirable? I mean in movies we're all for the good guy who pays the girl a lot of attention, remembers her birthday and buys her things to win the girl, he deserves her but when the "player" who's been flirting with every girl within a 5 mile radius all of a sudden pays her the slightest attention and rewards her with that sexy side smirk we all sway like daffodils in the wind - the only difference is the movie needs a satisfying ending so they can make good in the box office, so they allow you to assume that they lived happily ever after only arguing about who loves who more.

 Unfortunately folks, this isn't the way life works, in the real world the "player" will most probably cheat when he realises that he's still got his whole life ahead of him and all you want to do is change him, the good guy would turn cold on you when you come running back to where you placed him in the friend zone, he is now either going to be a prick or find some other girl who's been hurt before and welcomes his sweet kind heart.

(movies and series that predispose you to the "bad boy" syndrome: The Vampire Diaries, The Breakfast Club, 10 Things I hate About You, 90210, Pride and Prejudice, Wuthering Heights)

Ps. I'd still recommend those because they're great!