507
It doesn't take much...
(lemmy.world)
… especially if the neighborhood is filled with little shits with too many electrified toys.
EDIT: Okay, I'm convinced. Regular bikes would actually be a sensible cause here. Let me be a curmudgeon though.
Near me there's a giant roundabout joining 6 roads together, 2 of them highways, and it works fine as one roundabout. You just enter the roundabout and exit at your exit, it's not complicated and it doesn't need to be.