I could probably witness that several times per hour if I just sat and watched traffic all day.
Multiple times I have seen people entering the roundabout turn the wrong way and start driving into oncoming traffic.
The worst offender I saw was someone that missed their exit, stopped, and then did a U-turn IN THE MIDDLE of the roundabout and started driving the wrong way to go back to the exit they wanted to take.
It's mind boggling how many incompetent drivers are on the road.