When I was learning to drive my instructor was crazy. She insisted that I try not to stop at all at roundabouts because they were there to keep the traffic moving she said, unlike junctions. So when we got to a roundabout she would be waving her arms about saying 'flow, flow' for me to keep going.
One day I got to a small roundabout in a small town and as I approached it looked completely clear but I stopped and it was as if I could not move. She was starting with her 'flow' stuff and still I could not move when a huge lorry flashed in front of us without even slowing down. The driver shot straight through the roundabout without even a glance to the right.
We sat there stunned and she said, well I suppose the driver is the one whose instincts are working when you're on the road. If I hadn't stopped that lorry would have ploughed straight into her side of the car. Eventually I found another instructor and passed my test!