the problem is insurance and liability. Can you see a 8 year old kid getting in a driverless car, and car crashes, kid dies, that would bankrupt an insurance company or auto manufacturer once a jury gets a hold of it. And so far all teslas with thier autopilot mode, have been easily hacked, so how do you stop some genius hacker from grabbing a bunch of cars and sending them off a cliff, or into each other or into houses etc. honestly i dont ever think there will be completely driverless cars, there will always have to be the possibility of an override and manual controls.