The home page for the Google Self-Driving Car Project contains the following:

Imagine if everyone could get around easily and safely, regardless of their ability to drive. […] Aging or visually impaired loved ones wouldn't have to give up their independence. Time spent commuting could be time spent doing what you want to do. Deaths from traffic accidents—over 1.2 million worldwide every year—could be reduced dramatically, especially since 94% of accidents in the U.S. involve human error.

In some walks of life, we can reduce risks by changing human behavior. In the case of automobiles, we train and license people to make them drive more safely. We also fine and incarcerate them when they don't...