What Limits Exist?

How do traffic lights know exactly when to change from green to yellow to red? One key limit is the sensor technology. Traffic lights often use sensors buried under roads or cameras to detect vehicles. But these sensors have limits; they might not work well in bad weather or if something blocks the camera. Another limit is the set timing for lights to change. Some intersections have a fixed schedule, meaning the lights change every few minutes. This doesn't always match the actual traffic flow.