Like here's one I still remember from living in Mountain View. https://www.google.com/maps/@37.3911031,-122.0805526,3a,75y,... Roundabout with straight/left traffic lights (not the right turn lights sometimes seen on large roundabouts in Europe), an oxymoron. Someone drives through a green as usual and bam, hit by someone still clearing the roundabout. Is right on red legal here too? Extra islands also add to the confusion, making people U-turn wrongly. Lots of foot traffic and peds don't know when to safely walk in this situation. Having tons of signs there just adds to the overload.
Two-way stop signs with a roundabout. Who has right of way here? "CROSS TRAFFIC DOES NOT STOP," but roundabout normally means to yield to whoever's already in it: https://www.google.com/maps/place/37%C2%B023'14.3%22N+122%C2... Can they just remove the crap in the middle?
Or most commonly, zero stop signs but the roundabout is so tiny that it's unclear whether or not two cars can safely use it at the same time.
https://www.google.com/maps/@37.3911031,-122.0805526,3a,75y,... with straight/left green lights and walk signals (and right on red I think?)
https://www.google.com/maps/@37.3871436,-122.0803604,3a,75y,... with two-way stop, making right of way ambiguous
For some considerable subset of Americans the roundabout is an indecipherable creature that induces fear an panic. For a bit I lived in a more modern US neighborhood filled with them, including some larger ones on the main streets. Some people treat an empty roundabout like a stop sign coming up to it. Others panic and stop inside the 'about waiting for entering traffic. Then you get the occasional rebel that demands to go the wrong way.
I do like the roundabouts, but there are a lot of people still untrained in their ways.