The conversation isn't interesting enough. They've been asked a hundred times by previous boyfriends how they were. By doing what they did, you are lowering yourself to her exes' levels.
"How to ask a girl out" guide, quoted from seduction-chronicles.net because I am lazy to reword the same thing there:
Quote:
Instead of asking a woman out, tell her what you’re doing, and then tell her she can come along. When you ask a woman out early on, you are investing way to much. You don’t know how you guys are going to get along, so why spend $50 on a girl you probably don’t like. You should realize that when you say, “I’d love for you to come to dinner with me Friday night” is interpreted by a girl as “I don’t think you would really like spending too much time with me, unless I slip in this extra set of steak knives.”
It’s totally weak sauce. A girl will totally see through this, and group you in with all the other guys that “bribe” her. What’s your alternative when you ask a girl out on a date?
Tell her that you’re going to be doing something and that she should join you.
“I’m going to go down to Starbucks and get that new tea. You should meet me down there. I can’t promise anything but a nice cup of tea.”
If she hems and haws, or hesitates just interrupt and say, “Another time then”. I also like “You know, never mind. I guess you don’t like fun times…”. This is solid cocky and funny material, and it’s the right time to use it.