If you want to merge left while driving, what should you wait for?

When merging left while driving, it's important to wait for a bigger gap in traffic. This approach ensures that you have enough space to safely change lanes without causing disruption to other drivers. A larger gap allows for a smooth transition and minimizes the risk of colliding with vehicles in the lane you are entering. It also provides enough time to assess the movement of nearby vehicles and lets you merge at a safe speed.

In consideration of the other options, waiting for a smaller gap could lead to a risky maneuver, increasing the chances of an accident. A signal from the driver behind may not guarantee that they will allow you to merge safely, and relying on that can create uncertainty. Similarly, merely focusing on a car in the right side mirror does not provide a complete picture of traffic conditions and could overlook faster-moving vehicles in adjacent lanes. Thus, prioritizing a larger gap enhances overall road safety and driver confidence when merging.