I work in the technology field of computers and PLC's. I write software for PLC's and my partner programs for the PC. So I know a thing or two about how software is written, and debugged. We have software that was written 10 years ago, that STILL sometimes turns up a bug that nobody thought to program for. (NOTHING is more dangerous to a piece of software than an end user with time on their hands!)
When you look at all the variables involved in a self driving car, it boggles the mind that they have gotten it to work as well as it does.
It will never be 100% perfect, but I think it drives better NOW than most of the distracted drivers on the road today.;)
I think I will live long enough to see a car that can be bought off a showroom floor that has the ability to self drive. I would also bet that, statistically speaking, self driving cars will have fewer accidents than cars with human drivers between the ages of 16 and 25.