Mass leave
A mass leave refers to an event when a large segment of the community leaves the organization, typically to go on and form their own splinter or breakaway group. Historically, this has typically occurred at the subgroup level, where leadership for a given subgroup or a component within that subgroup will attempt to "break away" to form its own organization, usually under the rationalization that such an action will allow for freedom from perceived interference and control.
Arguably, the most infamous mass leave event involved the formation of the Dark Jedi Brotherhood, which occurred when a large segment of the Dark Brotherhood left to form their own organization. The DJB remains perhaps the only splinter group that has remained an active organization after a mass leave event.