Silly statement because of course colour matters; doesn’t it?
I’m presently working on a portrait and the subject will have leather boots. I’m putting in some highlights on the boots and it occurred to me that this is reflective light so what colour should it be? I’m making this image up as I go along. The reflected light could come from anywhere so the colour of the reflected light doesn’t really mater so long as it loosely fits my 3D visualization of what the scene should look like. The reflected light could come from anywhere both behind and in front of the subject of the portrait. The problem is believability, so the reflection needs to be of a quality and colour that is believable.