I have four Matfer Bourgeat copper pots, three of which I love, love, love, and use quite often, and one I hardly use at all. The three that get a lot of use I never polish. I don't have them on display - they're kept in cabinets with my other pots and pans. And I really don't mind the "patina" they've developed. Am I doing them a disservice by not keeping them polished? And, other than aesthetics, what's the reason for frequent polishing?