Rear-end collisions usually increase when a signal is installed. Normally, traffic engineers are willing to trade off an increase in rear-end collisions for a decrease in the more severe angle accidents. However, when there is no angle accident problem at an intersection, traffic signals may actually raise the number of accidents in a given area. I thought traffic signals made traffic flow more smoothly and safely. Only if used in the proper situations.
Traffic signals cause traffic to stop where it didn t have to before.
When used at an intersection where not justified, signals can cause frustration in drivers, who then seek alternate roads. These roads usually are not built to handle the increase. We have also found that drivers frustrated by unnecessarily long waits at traffic signals begin to disobey the lights. Traffic control devices are seen as reasonable by the drivers who use them. Usually after lesser forms of control have proven ineffective.