The first time I used Uber was about 6 or 7 years ago. I was living in the DC Suburbs and I had a plane to catch. The night before my flight I called and booked a cab for 6 am. At 6 am there was no cab so I called the dispatcher and asked when they'd be there, they said the cab was on its way and would be there in ten minutes. At 6:15 I called again and they admitted there had never been a cab on the way, there were none available, and they cancelled on me.
I downloaded Uber, signed up for an account, and had a ride by 6:25.