²⁰Prior to the advent of motor-actuated valves, practically all shutoff valves in industrial facilities were manually operated. While this is an inconvenience for operations personnel, it did carry one advantage: the human operators tasked with closing these valves by hand could feel how each valve seated. The amount of effort and the onset of closing torque sensed while turning the valve handle shut gave operators tactile feedback on the condition of each valve seat. Motor-powered valve actuators eliminated the need for this routine manual labor, but also eliminated the routine collection of this valuable diagnostic information. Modern electric valve actuators now provide the best of both worlds: convenient and fast valve operation with accurate self-diagnostic assessment of valve seating.