Well, I want to share my experience so maybe you can get 'broader' idea of that issue.
There was a woman that I used to like, she was a very sweet and go 'flattery' on me manny times than I can care to remember... As shy guy, it is difficult for me to approach and ask her out but at that time, I finally have the considerable measure of courage and asked her out. She gave me flatly and death-groping 'no'. That threw me off because what she did to me is clearly 'I really like you' behavior but she said she never find me interesting guy for her to go out with.
That is the last straw for me to fall for that 'cheap' tricks (example: flattery) unless woman make the move.. that's where I will confirm that she actually do like me. About Nas, when I firstly met her when she was my interpreter for my class, I really like her.. but I am not sure if she would go for shy guy like me so I decided to not make a move. She gave me different hints but you know how men are with women's 'subtle' hints... Men often to be required women to be very straightforward about what they want from men. Heh... anyway you already know the story so no need for me to say any further about it.
Let's backward to my HS year, one pretty gal used to like me so much but I barely noticed because I thought that she just want to hang around with me... But actually she really want me to ask her out or date with her. When I finally realized that she like me, I missed the opportunity because she gave up on me since other guy 'grabbed' her before I did. She didn't make the move so her 'subtle' hints went unnoticed... That was my big loss because she have this great personality that I had been looking for while my HS year. Oh well.
I think it is both gender have this 'approaching' problem (or shyness problem) :/