The general message I've received is that a question and its answer should be applicable to a wide audience, and not be "too localised" and so limited to small, specific audience. At the same time, as all know, duplicate questions are discouraged.
Both of these lend themselves to the notion that answers should be maintained and updated, preventing the need for the question being asked again. In an ideal world, this would be done by the community, but most of the time, aside from the odd error correction, questions/answers are largely maintained by their authors -- they have the most to gain from an upvoted answer, after all.
At the same time, if an author edits their post 12 or more times, it is automatically turned into a "Community Wiki", and they lose any reputation they've earned (or will earn) -- which surely discourages authors from maintaining their answers for future readers.
Hence the dichotomy I wish to flag for attention. If we want authors to take an active interest in maintaining their posts, isn't this sending a mixed signal?
Community Wiki posts clearly have their place, but are we discouraging maintenance? And if so, is that what we want?
Unfortunately I don't have a proposal, I'm merely floating this for discussion.
Edit: Just to practice what I was talking about (updating and maintaining my own post :) automatic conversion to CW was removed last year: http://blog.stackoverflow.com/2014/04/putting-the-community-back-in-wiki/?cb=1