Most of us did not realize how crucial depth perception plays a role in our lives and how reliable this function has guided us through each step we took. Depth perception allows us to look at things in three dimensions and gives us the sense of how far away and close they are. When it comes to depth, we use two kinds of cues; which are monocular depth cues and binocular depth cues. The monocular depth cues function by using only one eye. On the other hand, binocular depth cues are functioning using both eyes. Depth perception gives us the ability to compare one thing to another such as sizes, shapes, and distances. Imagine what would happen if you walking into something without know how far or whether the thing in front of you is blocking you not. In the video, it gives us some ideas about what might happened if we cannot perceive depth. A guy just walked into a mirror door because at that moment, he did not see or realize that the mirror was there.
Looking at another video below, let's pretend that the artwork was real, and the guy who is jumping and avoid the cliff has the ability to perceive depth and the rest do not. In this case, those who do not have the ability to perceive depth would of fall when they step into the cliff (artwork). And the guy who has depth perception of course would avoid the fall.