Maintaining wiki requires a lot of time. Even just adding new content is much more work than a reply over IM/email because one needs to find a right place (if s

Maintaining wiki requires a lot of time. Even just adding new content is much more work than a reply over IM/email because one needs to find a right place (if stricture is not completely flat), explain the context (which people exchanging messages have but would be missing for someone who would read wiki), organize content so it has some internal structure e. t. c. And there is a bigger problem - wiki to which new pages frequently added typically full of outdated or no longer relevant information. Updating or archiving old wiki pages requires a lot of time too (and this work sometimes can be done only by an author or someone who knows subject equally well). It is nice to have knowledge documented, but there is a tradeoff between time spend on wiki and time saved thanks to the wiki.