Why do some girls ignore me when I say "hi"?

Sometimes cute ones will ignore me when we're passing by and I say "hi" or "good morning". I'm not bad looking, and have gotten a lot prettier than the ones who have ignored me, so I don't take it personally. Is it usually a sign of being full of herself, or shyness and being uncomfortable talking to strangers? I hear pretty ones complain about how they hardly get approached, so why ignore someone who's being friendly?
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+1 y
The thing that brought on the question...I was hiking and at the end of the hike I saw a cute girl, when I walked past her I said "hi", and she ignored me. But she was lurking and she kept staring after that. My friend who was there saw her looking at me. Maybe she was just shy. Maybe she thought I was cute, but I'm home, and I don't have her number.
Why do some girls ignore me when I say "hi"?
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