The graphical or visual aspects of an interface are the most easily recognizable. They require no methodology (Graphic design vs usability) or design distinctions, (What is design?).
Everyone from CEO to programmer can understand an interface by it's visual treatment. For some the interface is "eye-candy" and for others representative of organized emotional response and visual perception.
Oftentimes, the confusion over who dictates the design can lead to confusion and often a gratuitous use of graphics. This problem can be compounded by an interface being dictated entirely by a designer (where usability resources are absent, underfunded or ignored entirely from a development process).