POCK said "The idea of these traffic circles is to keep traffic flowing, not for you to speed around and create possible accidents. Be courteous, and give someone an opportunity to merge into the circle instead of being on the rear end of the car ahead of you. It’s not a race people, be kind to the other drivers in town!!! "
The whole way a roundabout works is that traffic in the roundabout has right of way, flows freely and exits the roundabout safely and as quickly as possible. Those entering the roundabout should only enter when safe to do so. Studies in the uk clearly show that used correctly roundabouts allow for vastly improved traffic flow.
The problem is that most North American drivers don’t know how to correctly use a roundabout .