Please do not attempt to use this setting without consulting Site Administrators or the help desk
For this feature to work, other courses need to be listed and have completion tracking. Usually this feature will not be used unless we offer a course that replaces another course but still have the old course active. We may want to issue completions to all users who have completed the course (though this sort of implementation is extremely rare).
Usually the way this would be handled would be through prerequisites and programs.