Haha, for me, friendship kills all sexual feeling really
. Maybe there's not enough tension? Too much trust and comfort? I don't mean this in a weird way, as if you would always need to feel danger to have great sex - I can't really put my finger on it. Infatuation, maybe? Which is always somehow connected with a sense of newness? The only real FWB I've ever had I didn't know that well before we got it on.
However, the process of making new friends would still give room for infatuation. I guess I need to have positive feedback to become really interested. I might think, wow, she's really cute, but if there's no corresponding energy coming from them, I move on to Frienship Land. Might explain also why I don't have the hots for my closest friends, one being a straight woman and the other a gay man.