Disregarding the entertaining and sometimes amusing and informative side-threads, I still think you all have it backwards. Music is primarily a mode of self expression. The concept of performing (or entertaining others) comes afterwards. And music becomes traditional because it is, OF ITSELF, enjoyable, entertaining; so that people want to play it, or listen to it; and so it is passed on from one person to another by whatever means they choose to employ.
This is not to say thay anyone performing it should not do so to the best of their ability, to give the most pleasure to those hearing it, but this is common to any activity, not just traditional music.