First (?) rule of user experience: Computers are good at doing some things (counting) and people are good at doing other things (imagining, or parking). Let the computer do what it's good at, so that people can do what they are good at:

Lexus self parking video (funny) 

By my calculation, the car was actually parked twice in the process of getting the computer to park it.

Credit to Greg Ralph at Hiser to alerting us to this video.