Can anyone offer an explanation?

i just recently realized this when soemthing came up that made me look back over my past and the girlfriends i have had. So here is a scenario, you meet someone and they are very quiet when you first go out to meet them, pretty much just sit there offering only a few words every now and then but literally doing nothing. how does the other person become interested?

i have never approached a girl showing any intentions towards dating, i usually sit back, keep to myself, don't talk much especially around other people, and yet i have somehow managed to meet several girls, and most times they just give me their number and tell me to call them, after the first time meeting them, with that type of scenario play'd out, they already want to plan out another time to meet up, im not complaining by any means, but how does that workout when a person literally does nothing the whole time they are around them on the first meeting or two?