Every channel has a document specifying the exact orange, the exact typeface, the exact height of the lower third. Every channel also has a bulletin where the graphic is four pixels off, a social clip where somebody used last year's logo, and a package where the subtitles are a size that cannot be read on a phone. The guidelines are not wrong. They are just a description of what ought to happen, applied by hand, dozens of times a day, by people working at speed.
Brand Studio makes the guidelines the thing that actually runs. Colours, typefaces, logos, lower thirds, subtitle styling and the shape of every graphic live in one place, and every studio reads from it at the moment of use rather than keeping its own copy. Nobody applies the brand, because the brand is not something you apply.