What is a "stale" green light?

A "stale" green light refers to a traffic signal that has been in the green phase for a period of time, indicating that it may soon change to yellow or red. Understanding this concept is crucial for safe driving because it serves as a reminder to drivers to be prepared for a potential stop. A stale green light means that while the traffic is currently moving freely, the signal's longevity suggests it may not stay green much longer, prompting drivers to approach with caution and be ready to react.