If you photograph your designs a mirror finish may drive you crazy, particularly convex surfaces that can reflect objects from all angles. A satin finish is much easier to photograph as it doesn't reflect clearly defined objects and even the black from your camera is muted. You can see in the photo of the 3 rings that the left ring is reflecting the camera and surrounds, including me, but on the 2 frosted rings the finish is more dominant than the reflection.
The top wire has a frosted surface.
The difference with wire is not as obvious as flat metal but it still offers a point of difference in a design.