There have been a couple of threads. One is:
Creating the content wasn’t all that time consuming, but after a year some of them need revising.
Our site was migrated from a platform which had remained unchanged for a long time, so there was a transition period while people found their way around. New users don’t seem to ask many questions (but few of them interact with Discobot).
After about 7 months the number of user questions fell off drastically, and the few that do get asked are usually fielded by other users (either as a reply to the question, or by pointing the asker to the #userguides category.)
What guides you need will, of course, be dependent on your user base. Our users don’t use many of the more advanced features, so what I’ve got seems to be enough. I don’t want to fill up the #userguides with so many howtos that users get discouraged. If someone asks a question that isn’t covered then I’ll create a new one.