Motors are the 4 Centers in Human Design that generate and provide energy for the BodyGraph: the Sacral Center, the Solar Plexus Center, the Root Center, and the Heart/Ego Center. These 4 Centers are the "engines" of the Design — they produce the energy that drives action, creation, and movement through life. Whether a motor is defined (consistently available, reliable energy) or undefined (variable, conditioned, amplified from others) is fundamental to understanding how a person experiences energy. The Sacral Center is the most powerful motor and is the exclusive domain of Generators and Manifesting Generators — it is the primary life force engine of the species. The Solar Plexus, Root, and Heart/Ego motors can be connected to the Throat Center in ways that create the Manifestor's capacity to initiate action directly. Non-motor Centers (Head, Ajna, G, Throat, Spleen) do not generate energy in the same way.