Galing talaga ng mga Pinoy draybers!
More than just a personal grooming accessory, the purpose of having the rear-view and side-view mirrors, they give the driver view of the peripherals to calculate approximate distances and speed. Highly useful in changing lanes in case the driver of the red car hadn't noticed.
So I searched the proper way of adjusting the side-view mirror and to my surprise, I got mine incorrectly. It doesn't help that I trusted the words of Dr. Sheldon Cooper.
Sorry I can't find the clip where he discusses how to adjust the side-view mirror. But it's in this episode.
According to this website