If your object has a matte surface, you can generally avoid having to put any reflective patterns on it. However, if you have what is essentially a chrome surface, the environment in which the object finds itself should be rendered in all of its glory into the material. Personally, if I know an object is going to be reflective, I tend to paint both the matte qualities and reflective qualities on separate layers, so that the level of matte-ness to reflective-ness can be controlled later (if I even want this level of control). As I become more experienced, I just keep this in mind without all the extra plotting and rendering, there's just too much to design and paint in any given project. I'm lazy too. Additionally, if you are willing to push the hue shifts with the lighting, particularly where the specular highlights are, you can start to suggest mixed metals and metal flake. The more intense the hue shifting, there will be a more intense effect of the metal flake effect. The green and purple example below is what I would call "flip-flop" paint that those Low-Rider guys like to use on their cars and motorcycles.
