Thus is a large weakness of the “forum” format when it comes to sharing information.
In time, and a short time at that, knowledge is buried and forgotten. That great, informative post you wrote last year is hopelessly impossible to find by anyone that doesn’t know exactly where it is.
This also causes the cyclic nature of forums. A body of people come together to discuss a topic. Over time they cover all the points and nuances. New people are told “we talked about that topic here” or the less friendly “learn to use the search tool”. Eventually, the old guard has run out of things to talk about and leave the board because it is boring. Then in time a core of new people come together to discuss the topic. They re-hash all the old topics, more or less from scratch.
If you want information to endure, I recommend putting it in a Wiki. They are remarkably less fun than a forum, but the information is easily accessible to all. Especially if it is cross-linked well. Take a look at tvtropes.org and how that Wiki is designed. Lots of cross-linking not only limited to things directly discussed as part of the topic definition, but also to things that are similar for comparison and to things that are opposites for contrast.