Those cars are not able to handle general purpose driving.
Say you are on a one-way road, and at the bottom of it an ambulance is blocking the road - so you need to back all the way out of the road (or u-turn).
No driverless car today can handle such a situation. There are many more real-world examples. The cars today are just demos, not usable products.
but it already has?!
I mean there are already self driving cars being tested on public roads. Technically not driverless, but almost.