Why getting a stalled actuator moving in the first place can demand noticeably more torque than keeping it moving once it's already going.
A motor spec sheet often gives you a single, clean number for continuous torque and calls it a day. But a system sitting perfectly still and a system already gliding at speed are two different mechanical situations, with two different amounts of friction to overcome. Sizing a motor for only the second one — the easier one — is one of the more common and more consequential mistakes in actuator selection, because it can produce a motor that runs beautifully once moving and simply never starts.