I stopped approaching women because I got nowhere with them. I decided if a woman really likes me, then she will approach me. After so many rejections, I decided that if a woman doesn't approach me at all in my lifetime. It means god didn't have a spouse for me, and It's fine. Why don't women approach men? I'm 23 and I'm no longer approaching women, it gets me nowhere so they can come to me.
Not many mack daddies are born. The difference between you and the guys getting some is that they took their rejections, learned from them, and moved on. Even the suavest, slickest guys out there say they get turned down more than 50% of the time. That makes sense, since not every girl out there necessarily wants to meet someone, and beauty is in the eye of the beholder and all. Your success is defined by your reaction to inevitable rejection. Even a hideous fat ugly pimply guy could get some if he didn't mind getting rejected a few thousand times before hitting paydirt.
Look, you can sit here and complain. Nobody's going to stop you, it's not illegal, it's not even frowned upon. But it won't get you laid. Of course, you do need to make sure you have the basics down. I don't know you or what you look like, but general tips are to lift weights and jog, dress well (you cannot do this by shopping at wal-mart), get your hair done right at a salon, etc. There's other stuff that depends on you personally, I'm so hairy that if I were superficial enough to care about looks I'd need to use a hedgeclipper on my eyebrows and ears every couple weeks.
First I'm going to say you shouldn't just give up like that your 23 for heavens sake life is just starting and people haven't even fully matured yet but ill stop ranting and give my answer. For me it's a combo of 2 things:
1) I like to pursued it makes me feel special like the guy actually cares enough to chase me. It's overall just a nice feeling for a girl.
2) fear. It's a common thing that's if a girl goes up to a guy and is rejected it's kind of her reputation on the line that she wasn't attractive enough for a guy to want. Or if its a short relationship she could be labeled slutty and easy. Where if a guy approaches and he's rejected it's not such a big deal he's just going through the motion him and his buddies laugh it off. A girl has a lot more on the line of coming off in attractive or easy depending on how it plays out.