However, there is a potential disadvantage.
Your interior rearview mirror already provides a view of much of the road directly behind you. When both side mirrors are pointed too far inward, they can repeat some of that same view instead of showing more of the lanes alongside your vehicle.
That overlap can leave an area beside the rear quarter of your car difficult to see in any mirror.
Imagine a car approaching from behind in the next lane. You see it in your interior mirror, but as it moves alongside your vehicle, it may disappear from that mirror before becoming visible in your side mirror.
For a moment, the other car may seem to vanish.
That is the problem drivers are trying to address when they adjust their mirrors to reduce blind spots.
According to the U.S. National Highway Traffic Safety Administration (NHTSA), positioning outside mirrors to provide a wider view of the roadway can help minimize blind spots. Its guidance describes an alternative adjustment method that directs the mirrors farther outward than the common setting.
