It's good to follow all traffic signs.
"John and Mark are in the car and John is driving as they approach main street which shows a ""no left turn"" sign from the current road they're on."
John wants to drive south down main street.
John continues straight down the road he's on and drives around the block before accessing main street from a different road.
John sees a gap in traffic and takes the opportunity to make the left turn anyway onto main street.
Mark is happy to take a scenic route and remarks how the houses look nice on the other streets.
Mark is horrified at the stunt and is temporarily terrified and stiff with stress.