I've always had great experiences with uber (and Lyft) until last week in San Francisco. I requested a car and didn't move from my location. The driver was one street over from me but then turned in the wrong direction. I was looking for the option to contact him when *he* cancelled and I was charged a $5 cancellation fee and of course had to start over with requesting/waiting for a car.
I don't know why uber lets drivers claim that someone is a no show (I assume that's what happened) when the gps data clearly shows that the driver didn't go to the location and made no attempt to contact me.