I think you can size them up better irl than pof. irl there are thousands of tiny behaviours - intent and reaction signals between the two of you. you can feel the other person's sexual interest and its all being recorded in the girl's mind and linked to your physical self. Internet interaction links any feelings she has to a facsimile of you, an imagined estimation of what ur like. When u meet in real life u have to work to retrigger these previous interaction memories and anchor them to urself due to lack of recognition. Not that everyone isnt an imagined estimation based on previous evidence to everyone else anyway, they absolutely are, but physicality is important to reproductive processes.