If a self-driving car still has an ability to shift into "manual control" mode and do it really fast, then self-driving cars are good for some people. But if it only has an emergency stop button like Waymo, then they will do harm instead of good. Imagine a situation when your car is driving down a highway and suddenly, some drunk retard is driving in opposite lane (your lane), coming at you at full speed. If you are driving a normal car (or a self-driving car that has a manual control option), you can swerve into the ditch and avoid a head-on crash. You may break some bones, but you will be alive. But if you have a fully self-driving car, you can either bail out of it (that will most probably result in your death) or just press the emergency stop button and pray to god (this option will probably result in your death, too).
A well refined system can detect danger and take evasive action much faster than a human can. The emergency stop button in the Waymo is there because it's a prototype and still makes mistakes, not because you have to press it or the car won't do anything. The car will take evasive action without any input from the driver. No company in their right mind would release a fully autonomous vehicle to the public if it didn't know what to do in a situation as simple as the one you described.
Self driving might be relaxing and stuff and old people might like it but .. I am not old .. I like driving cars myself. I dont want to watch how the computer drives me into the next tree. I am a fan of old cars where you have a steering wheel, 3 pedals and a seat and engine ..
Wait... maybe self-driving cars could have a feature were you can switch from driver mode to AUTOPILOT mode!
