When should lights be used on motor vehicles?

Using lights on motor vehicles in any condition where visibility is poor is essential for ensuring safety. This includes circumstances like rain, fog, snow, or any other weather conditions that may reduce visibility, as well as during twilight hours or when driving through poorly lit areas. Proper use of vehicle lights enhances the driver's ability to see and be seen, thus preventing accidents.

In contrast, using lights only during the night does not take into account the various daytime conditions that can impair visibility. Clear weather during the day may not always require the use of lights unless visibility is affected. Driving over 25 mph does not automatically necessitate the use of headlights, as speed does not correlate with visibility. Each situation necessitates an evaluation of environmental conditions, and the use of lights in poor visibility is a fundamental safety practice.