In the quest for ever-larger television and computer monitors and the advent of HD (and Ultra-HD), it is now possible to watch a movie, (clearly), where the characters are larger than you are. (Who needs anything that big anyway?) The answer, more often than not, is entertainment, science, military and government with a good dose of retailing on the side. However, unless you are insanely wealthy, the thought of replacing one of these monstrosities would make the most stalwart Navy Seal weak in the knees. With a video wall, you can significantly reduce component cost and increase your flexibility at the same time. You can increase the size of your viewing area by using the system to link several moderately sized monitors together. In the event of component failure, you need only replace the individual monitor affected, not the entire system. (Much as it is easier and cheaper to change a light bulb instead of having to rewire the whole house.)
NASA uses a videowall to track the space shuttle as it circumnavigates the Earth. (Squashing that down onto one monitor would drastically reduce the size of the image, to the point where it would be impossible to make a coherent assessment of the information presented.) It would not be impossible to imagine them having a larger videowall to keep track of individual pieces of space debris. [More objects require more space to delineate them.] Following this reasoning, having the capability to add in monitors as the number of pieces of junk increases (requiring a larger format to see them all) instead of having to start over with a larger screen makes the videowall system an even bigger benefit. Knowing many of the applications for which videowalls are used, they are designed with multiple redundancies and ‘hot swap capabilities; components can be replaced without the requirement that the system be shut down to do it. They can be run on a 24/7 basis for over 5 years and use their own system specific cooling system.