Us guys don't want to get stuck dancing with someone for an hour. We're bored after ten minutes. That's pretty much the reason right there.
Faith was also complaining about guys that just IM "hi" and after she responds with "hello", she doesn't hear from them for five minutes. My suggestion is to spice the conversation up a bit by lying (the lies are shown in italics):
Guy: HiConversations are a dance too. You don't always have to follow, sometimes you can lead.
Gal: Hello, I was waiting for you to IM me.
Gal: Yes, I'm psychic. Do you want me to tell you what you're thinking now?
Gal: You're thinking about asking me to dance.
Guy: You're good.
Gal: Okay, let's dance.