If you want to keep brass looking new and shiny, you could use a product called "Renaissance Wax". This is what museums and art galleries use to protect the items in their collections from tarnishing.
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It keeps metal like silver and brass looking shiny and new but it is removable when you need it. Just use Renaissance wax as part of your cleaning regimen. In between cleanings, all you have to do is take a clean cloth and wipe.
If you ever decide to let your brass tarnish, you just clean the brass like usual but DON'T use the wax. In time, it will turn color and look "old" again.
Some brass has a coating of lacquer over it to prevent tarnish. It keeps the brass looking shinier for a longer time but, over time it starts looking shabby because the lacquer chips and gets old. In order to restore it, you have to remove all of the lacquer, shine the brass up again and re-lacquer. This can be a large pain in the butt!
Still, some people like the convenience of only having to wipe the dirt off the outside surfaces when they clean and they never use their brass items enough to get the lacquer chipped up.
Personally, I'm in between. I don't mind if brass tarnishes but, if I decide I want things to look nice again, I want to be able to shine them up.