Why the hell are guys so dense?

Everything you say, if they aren't 100% paying attention seems to go in one ear and out the other -.- Apparently they don't know the idea of "subtle hints" either. If i made the point I've been trying to make the past month or two any clearer, it'd be a train with a fucking huge sign on the front of it coming right at you! Or perhaps they do understand and just don't care?

Any girls out there know how to make a guy realize what you are trying to say without coming right out and saying it?

I am a guy, but i am exempt from this because i fucking noticed it!