When comparing closed versus open authoring approaches, it is worth looking at the history of Wikipedia, which has succeeded in creating the largest encyclopedia in history. Wikipedia was preceded by the Nupedia  project, which also aimed to build a free content encyclopedia. Nupedia was not an open wiki like Wikipedia and adopted an extensive process of peer review before final publication of an article. After years, Nupedia had only completed 24 Articles, with 74 more articles as work in progress. Clearly this authoring model was not scalable, and was a strong motivation for Jimmy Wales, the founder of Nupedia to open up the authoring model by starting the Wikipedia project.