Roundabouts are more efficient than stop lights.
Roundabouts don't require sensing, timing mechanisms, emergency bypass
Roundabouts still work when power goes out
Roundabouts are faster than a four-way stop sign intersection
Cars have to actually stop at stop signs.
High-speed accidents are fewer on roundabouts.
People would not speed up to get through the roundabout like they do for lights.
Roundabouts do not malfunction like traffic lights.
People wouldn't block traffic by turning left from shared lanes.
Roundabouts do not require dedicated signal time from left-turn lanes.
Roundabouts do not lose time to yellow lights.
Roundabouts don't require electrical timing mechanisms, emergency bypass
For high-volume roads, roundabouts would slow things down a lot.
Roundabouts are unfamiliar to U.S. drivers, so there would be accidents.
Roundabouts cost more money to build.
Roundabouts take up more space than stop sign intersections.
More cars can get through traffic lights than roundabouts on high-traffic roads.