There is another sense in which Wikipedia’s goal of creating a free encyclopedia seems to occupy a “sweet spot”. Explaining this involves looking at two other Wikimedia projects.
Wikisource is a library of free-content texts, including works of literature, reference works, and historically or politically significant documents. It uses crowdsourced effort to upload scans, correct character-recognition errors and proofread. The end product is electronic text that is faithful to the original text of the document or book, organised in a way that makes it useful and findable. Slowly but steadily it has built up hundreds of thousands of documents, many coming from cultural partners such as the British Library or the US National Archives.
Where Wikipedia has to be an original literary work, Wikisource is about replicating texts that already exist. This means that there is a clear measure of progress and fewer possibilities for disagreement. The downside is that there is less scope for creative expression. Contributors do not have the same opportunity to make a personal mark as Wikipedians do when they decide the phrasing or structure for an article.
Wikiversity aims to be a space where people can “mutually cooperate in an active effort to learn”. This includes creating open educational resources, carrying out educational activities (for any educational context or level) and carrying out original research projects. Its tens of thousands of resources cover the whole spectrum of quality. A group of economists at the University of Exeter have shared a handbook of classroom economic experiments through the site, benefiting from textual improvements by the community. This is an example of the site’s very best content: there is a lot more of dubious utility, including fringe points of view.
Wikiversity’s scope is very much less constrained than Wikipedia’s; it accepts a lot of material that would be deleted outright from Wikipedia. It is harder to argue that anything should be deleted, since almost any online materials could have some use in education or research. A project similar to Wikipedia but less constrained might sound like it would attract many more contributions and become a greater success. This is the reverse of what happened. One possible reason is reputation: people are prouder of getting their material onto a platform that rejects a lot of contributions. Another is that there may simply be more demand for didactic encyclopedic text than for other types of educational resource. Another is that contributors need the confidence that their actions will improve the site, and that this requires a tightly-defined scope.
Wikipedia, Wikiversity, and Wikisource’s goals are all laudable, and the differences in their success are due to multiple factors that are technical, historical and social. However, the community’s goal plays a part, and Wikipedia’s much greater contributor base and audience result at least partly from the mix of creativity and constraint.