Buff well before adding a finish. The finish is to seal the article including any dyes, paint, antique, etc. If you don't buff well before adding the finish, the surface particles get picked up, spread around and mixed in with the finish. Then as you do excessive buffing of the finish, you remove some of the finish, including the dyes that got mixed in with it.
Moving your post to "Dyes, Antiques, Stains, Glues, Waxes, Finishes and Conditioners". You should look through posts in this area as well.