I'll make it short and sweet. Bad experiences.
For most guys, the pattern they've experienced:
She's Fine = She thinks she is better than you = Rejection
Therefore, we don't bother. Not to say that there's not good one's out there who are really attractive, but many females take it to their head.
If you make it a point to show yourself as approachable, then your problem will disappear. Holla!
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