Stubs are pages of minimal content and are not considered to be "finished" by the person who started it.
A stub can be set up by the author who plans to finish it later, places it in hopes or the thought that someone else might have the knowledge of the subject matter in order to finish it, or it is started by the thought of the author that it belongs on said Wikia, as it fits the Wikia's subject matter and merits its inclusion on the site.