Regenesis needs, applied to users
Need for revival exists when there are no user communities or individuals.
Need for reversal exists when the users are elderly individuals, “grandparents”. They may or may not form a user community. The “parent” generation may know some of the language receptively. Most children do not know the language, even receptively. Neither parents nor children form a user community.
Need for revitalisation exists when only few of those “parents” who might belong to the user collectivity on the basis of their ethnic and/or linguistic background, are (competent) productive users, and when most of their children do not form a user community. Many or most “grandparents” are users at some level and form a user community, even if it is at an informal level.