What does it mean if a guy is too shy to talk to you?

Well, speaking as a guy who has a hard time talking with girls, I would say it really doesn't mean anything. I have a hard time talking with anyone, but especially girls. I'm not really sure why, what helps though is when she smiles, and doesn't look bored. My point is, the non-verbal cues can be a big factor in how comfortable he is talking with you.