The rear-view mirror is a great tool. It gives us a way to see what is behind us so we can use that information to make better decisions. For example, it helps us avoid pulling out in front of that speeding little red convertible weaving in and out of traffic.
Rear-view mirrors also provide insight into obstacles and dangers in those rare instances when we are forced to backup before we can start moving forward again. Despite its great value, however, the rear-view mirror was never purposed to hold our attention for long periods of time. Too much focus on the rear-view mirror can cause us to crash and stall our forward movement.