When does a revival become a living tradition?

Supposing a tradition has completely died out. Someone finds a dusty book on the topic, reads it and thinks "hey! this looks like fun". The share it with their friends and their friends and soon it's pretty popular. Our first person starts some classes, and eventually the people they taught go on to teach other people to do this thing too, and eventually their pupils do the same. There's now a social network around this activity, competitions, festivals, events.

So when does it stop being a revival and start to be a living tradition? Perhaps two or three teaching generations? Enough people doing it to disagree how it should be done? When folk are so used to it they take it for granted and stop thinking about it?

This is an important question for me as a folk harpist and one that is pretty fascinating full stop. Within the harp world there are many broken traditions currently being reconstructed and many traditions which *almost* passed into the unknown but didn't quite and are now being given well deserved love. In Europe we see a really strong resurgence of many folk traditions but the mystique of a folk "tradition" really worries me, it seems so false. I'm always curious to see how people respond to the notion that we're just making it up for fun for ourselves as we go. I think that is the tradition I'd really like to pass on - diy artistic fun.