Appropriate?
In the 1990s I wrote some software from scratch for a Federal Government initiative designed to help heritage organizations capture and manage their data. It was also taken up by State Governments - Often used by volunteers, one of its design imperatives was that it could be configured with different levels of functionality based on the experience of its users. I thought it was fairly simple and self-explanatory having only 5 main screens. I was wrong. Fortunately, a business partner, who had been a professional teacher wrote most of the manual; ~275 A4 pages long, but broken down in to sections with appropriate cross referencing, examples and screen shots.
My first reaction was that it was too complex, but users really liked it. The only problem (for us) was that a "small change" to the software required significant changes to the manual. Many customers did not have access to cheap printing, so we had to distribute them as insert sections to go in the original ring folder. As printing became more available, they were just distributed as MS Word or PDF files. Of course, these days updated versions are on a web server operated by the new owners. Lots of refinements, but still recognisable as a direct descendant after 30 years...