If I go to Activities and select a saved view or system view of appointments, tasks, phone calls or activities, the Mark Compete button displays on the ribbon, allowing me to mark multiple activities as complete in one go.

If I run an advanced find for Activities, the Mark Complete button displays on the button allowing me to mark multiple activities as complete in one go (although I can only close activities of one type in a single step).

If I run an advanced find for Phone Calls, Appointments or Tasks, there is no Mark Compete button. Why? Please add it back.