Is it true that traffic signals always make traffic flow smoother and safer?
No. They only make traffic flow smoother and safer when used in proper situations. Traffic signals cause traffic to stop where it may not have had to stop before. When used at an intersection where not justified, signals can cause frustration in drivers, who then seek alternate routes. These routes usually are not built to handle increased traffic flow. In addition, drivers frustrated by unnecessarily long waits at signals may begin to disobey the law. Traffic control devices are most effective when perceived as reasonable by the motorists, bicyclists, and pedestrians that use them. When do traffic engineers decide signals are justified? Usually after lesser forms of control, such as stop signs or yield signs have proven to be ineffective. Then traffic engineers follow specific, uniform guidelines to determine whether a traffic signal is necessary. What about intersections that don’t meet this engineering criteria? Problems can occur. Signals almost always create overall delay to drive
