I am not a programmer of any sort Santa but not sure I agree with your last sentence. I can honestly say I've never used a computer program that didn't have some sort of glitch or bug in it (however minor). I come across them every single day, probably every hour.
On a computer it's annoying...but in a vehicle it could manifest as the steering malfunctioning, swerving into oncoming traffic, randomly slamming on the brakes, etc. More than annoying but from the machine's point of view just a bug in the programming.
That said, if they do make it reliable enough, I'm in agreement from the stats point of view. I mentioned on another forum discussing AI doctors & surgeons...but could be applied to autonomous driving...if avoidable deaths were halved that's surely a success not a failure?