You can see one example at the end of the video on their technology page where the cyclist can't make up his mind. It recognizes the left turn sign from the rider (you can see the sybmol change when he extends his arm).
There are good reasons why things like these happened:
> The law of some states, such as Louisiana, explicitly lists a killing in the course of defending oneself against forcible entry of an occupied motor vehicle as a justifiable homicide.
While I'm interested in self driving cars that still feature manual controls you can override, like Tesla, I have no interest in a future controlled by Google's AI without my input.