i don't think that's a girls/guys thing, shy people is hard to talk...
One day i was sit on one of those banks in the street, then i girl came out of the blue , sat by my side and started to chat with me - she was just amazing, she was very pretty, but what was more impressive was her sympathy, it made me feel like...WOW!... You know what i did? absolutelly nothing, i don't even asked her name - she needed to ask mine! - i wasn't rude in anyway (i would never be) but i couldn't keep her interested because i was so afraid to speak... She probably left thinking that i was such a jerk!
So that works both ways - I don't have the guts to say hello to that interesting girl that passes by me everyday, and if some girl talks to me i just "turn my brain off".
(sorry i always end up with this long stories about myself -.- )
But i have to take the boys side

Girls, it's easier for you... because we men have to ask for the dates and we men have to win your hearts...
and i'm so ashamed just to say it