Do people ever do this with success?? (go for the kiss when she hasn't' given you any clues that she's into you)

The reason I ask is that sometimes I wonder if i'm waiting for too much of a clear 'green light'

I have a friend in his late 20's who has slept with every hot teenager he has hosted on couchsurfing.

He always says ''I took them out for a drink to show them around. Just basic small chat. Then back to my place. Sat down on the couch and drank a wine. Then we Kissed. Then we Had sex''

It's the 'Then we kissed' part which seems to come out of nowhere that confuses me! I never go for a kiss unless a I have at least a hint that she is into me.

I hosted a few girls when staying in my parents place in London. Everytime we go out. Have some drinks. I'd try to be fun. I'd try touching them to 'show my intent'. (Would allow me to touch their shoulder or something, but maybe pull away the second it looked like I wanted to be more than friends. say, brushing their forearm maybe). Then, like my friend, we'd go back to my place and sit and have a drink, but there just felt like zero sexual interest coming from her. But starting to think that maybe I should have just tried to kiss her even though it might have seemed weird. like:

''OK, girl hasn't shown any interest in me sexually. We're now sat on my couch talking about the price of houses in London. Just go for the kiss mid sentence now?!!''