This is from Matt Wiseley of EditMe, a company that offers an excellent combination of a powerful hosted wiki and affordable professional services to customize it to meet your needs.

Check out Edit Your Web, Matt’s new blog on wiki-related news, trends, wiki engine reviews, and examples of compelling wiki sites. – Stewart

All content added to a wiki has some inherent useful lifespan. Considering this, a wiki that’s been around for a few years probably has some great old pages that have been faithfully maintained and kept up. Others may have been useful when they were created, but have since become “chaff” – remainder content that is no longer relevant, accurate or understood. Perhaps it’s about a product or service no longer offered, it may document some process that has long since changed, or maybe it was cryptically created by some employee who has since left the company.

It’s likely that people using the wiki just breeze by this content assuming it must be useful to someone. They’d better not touch it, just in case.

This kind of content can bring a wiki down. Consider the “broken windows” analogy given in the timeless book on being a great programmer, The Pragmatic Programmer. City planners will tell you that an abandoned building can sit untouched for years, but as soon as a single window is broken, vandalism of the building escalates quickly. In programming, this happens with bad or unused code that programmers come across but leave, hesitant to touch someone else’s work. In your wiki, it happens with “dead” pages that are long past their useful life and need to be deleted.

Ben Allums, Director of Engineering at Quadralay/Webworks.com, gives an excellent illustration of this in his recent post titled Wiki Maturation – Tossing Tennis Balls. He tells the story of a container of tennis balls that remained in his company’s server room through several office moves – for well over a decade – before he finally tossed them out. Allums argues that this requires a sense of ownership over the content. Perhaps this can be done by department… tell people on the marketing team that they’re responsible for keeping marketing related content up-to-date, which includes boldly deleting content that’s no longer needed.

Many wikis allow you to “mark” a page as deleted, which is to delete it without really destroying data. Do this liberally in your wiki for content that you are fairly sure hasn’t been used or needed for some time. If a page can sit with a deletion stamped on its forehead for a month or more, it’s time to do the deed and delete it forever.

Keeping old and dead content out of your wiki will make it a more vibrant and useful resource. It will communicate to everyone who uses it that it’s not an abandoned building. And giving out the mandate to take ownership of the content and take out the garbage will help contributors feel more empowered and engaged in the process.