Everybody is potential instance creator for task 0. Usually this happens, because no people assignment criteria is defined for the potential instance creators of the task, or because its usage returns an empty set of users.
Explanation
Because no potential instance creator could not be found, everybody will be a potential instance creator of the task. This can occur, when either the task's people assignment criteria (staff verb) for potential instance creator returns an empty set of users, or when this people assignment criteria is not defined.
User response
If this is not what you want, check the people assignment criteria (staff verb): Maybe the people assignment criteria need to be changed, or you need to define a people assignment for the potential instance creator of the task.