These cars are just too polite. Engineered for driving safely on America’s highways and bi-ways in the twenty-first century, Google has clearly produced one of the safest vehicles on the road today. Since 2009 these cars have been involved in only sixteen crashes and, in each case, a human driver has been at fault (company data). At the same time, the Google car has been pulled over once by the police for driving too slowly!
In the final analysis these driverless automobiles really do obey the “rules of the road” when their human-driven counterparts apparently always do not. Take the four-way stop scenario: the Google car always seems to politely wait for its turn. Not unsurprisingly in the human-driver world, this rule does not always seem to apply. He who hesitates may be lost as the saying goes, but if you are in New Jersey you always have jughandles at stop lights (you may have to do some research on this, sorry).
So it seems that the lesson to be learned for the new driverless cars is tha they have to be aggressive in the right amount. And that right amount depends on the culture, and there are lot of road ways between Google headquarters in Mountain View, California, and the New Jersey Turnpike.