You mean like we have every day already? Human drivers constantly make mistakes, and in many cases they aren't even aware of it or their affect on the drivers around them. Most don't cause an accident, but the behavior doesn't get corrected and that is what it eventually leads to.
Slowing for a turn then deciding to continue on, merging without checking blindspots, running red lights, speeding next to the short on-ramp lane, not following a yield to right turn sign, ignoring people in crosswalks, etc. All of these things happen all the time, I see at least one example every time I go out somewhere.
