When driving in a rainstorm, when should windshield wipers be used?

Using windshield wipers anytime it rains is essential for maintaining visibility and safety on the road. Rain, even when it's light, can cause water to accumulate on the windshield, reducing the driver's ability to see clearly. As visibility decreases, the risk of accidents increases. Therefore, it's important to activate the windshield wipers as soon as raindrops start to fall, rather than waiting for conditions to worsen. This proactive approach helps ensure that the driver can react to hazards on the road and navigate safely throughout changing weather conditions.

The other options suggest a reactive approach that could compromise safety. For instance, waiting until it's pouring rain may lead to significantly reduced visibility before the driver takes action. Similarly, relying on personal judgment of when wipers are necessary can lead to inconsistent use and potential dangers during variable weather conditions. Consistently using windshield wipers during any rainfall is the safest practice.