Why the fuck do SOME women like me and OTHERS don't?

Let me bring examples that happen in my school... (to prevent lawsuits and snoopings, I will avoid mentioning class and student names)

so in my first class, some are quite enjoyable to talk to even the hot ones, others will try to end the conversation

and in my second class, ESPECIALLY my 2nd class.. some girls i have to initiate with and they even try to reject me by looking into their phones and usually not initiating with me.. but a select few of them still like to talk to me.. today there was a cutie who called my name out (she sat behind me and i felt shocked) and she asked me if i had a book that was needed for homework.. i told her yeah and gave her the book because she said she needed to take shots of it.. it was 2 mins and she gave the book back to me.. but the other cutie and i didn't talk to each other at all today

aaanddd in my third class, there was a cutie who i sat next to and i was focusing on the computer as we worked on something, i didn't talk to her but i did notice her rubbing her legs in her sweats and she switched to another spot... HOWEVER ANOTHER CUTIE (whom I just found out had her bf and her posted on social media, lol) kept on smiling at me and i finally decided to talk to HER, and we still talk and she like plays with her hair on the occasion.. lol

Why do SOME women (even the sexy ones) prefer to talk to me while others (ESPECIALLY the sexy ones) require I talk to them