This system is particularly useful for people who do not have the facility to fix the TV on one wall and are sitting to see. Sometimes a slight tilt or a slight advance to the TVs makes a difference between looking good and straining. For example, a reflection of light from the window can sometimes make trouble watching TV.
In such a situation if your TV was a full horse mounted on a mount, you can transfer a little on the TV and arrange it to look the best. If you are not very specific about the quality of the full motion TV bracket, then one can be a recipe for heavy TV stuck with one hand.