One reason this is so is that the television monitor presents a flat, onedimensional image. On top of that, most of the anchor shots are shot fairly close. People on television tend to be shot from the fifth button up, or even closer. Of course, there are wide shots and establishing shots of the studio, but mostly television news and hosting is confined to close-ups. So if you start moving your body or hand quickly towards the camera, it will look distorted, like a fun-house mirror.