Why is it important to check blind spots before changing lanes?

Checking blind spots before changing lanes is crucial because it helps to avoid collisions with vehicles that may not be visible in your mirrors. Mirrors provide only a limited view of the road around you, and they can have blind spots where other vehicles can be present without you knowing it. By physically looking over your shoulder into your blind spot, you can ensure that there are no vehicles, cyclists, or pedestrians in that area before you move. This practice significantly enhances road safety, as many accidents occur when drivers change lanes without confirming that the way is clear.

The other options focus on different aspects of driving safety or vehicle operation but do not directly address the specific risk associated with blind spots. Adjusting mirrors is certainly important but does not replace the need to check blind spots. Verifying the distance to the car behind you is also a good practice but does not specifically ensure awareness of any vehicles that might be right next to or behind you in your blind spot. Lastly, assessing traffic conditions ahead is essential for safe driving, but it does not mitigate the risk of a collision that can occur when changing lanes without checking blind spots.