a) It's wasting energy. The unswitched leg is constantly pulsing juice in and out of the motor windings. Even though it's not runnning, it's experiencing hysteresis losses thereby. For an ejector pump such a persistent bleeding of energy would entirely out match its primary function.
Can this be explained further. How can energy be used with only one connection. There is no path of return to allow current flow to create any hysteresis effects.
