An update to a blind date

Ok so the date seems to go well. As you're walking away she asks to do it again. Sure next Monday... Call back a couple of days later for the date to thank her and say you had a good time. She says I'll see you for coffee on Monday. Sunday you call to confirm a time, and get voicemail. Monday comes and passes no call.

That's where I get aggrivated. If you're going to stand me up and you're not interested don't start by asking me out again. That's just rude. Could someone tell me why people do this?