PFC or to be more correct power factor improvement, is used only in devices that present an inductive load. Some capacitors that are fitted at the supply terminals of domestic appliances are for radio interference suppression, usually found on universal motors and microwave ovens. The appliances with induction motors, such as dishwashers and pressure washers, use a motor which needs a capacitor continually connected in series with the second winding. While this capacitor provides power factor improvement, it's main function is to give the necessary phase shift in the second motor winding to make the motor self start and to contribute to the running torque of the motor. This makes the motor smaller and uses less material.
HND Electronics UK, used to teach this stuff in college