Let's make the cycle of the rotating table and the cycle of the pendulum even closer. When these cycles coincide, the locus of the pendulum becomes a perfect circle, and it spins around the same area. When this happens, the centrifugal force of the rotating system and the restoring force of the pendulum balance out, and only Coriolis' force acts on the ball of the pendulum. In other words, from the point of view of the rotating system, it is no longer a pendulum, but a body on horizontal plane that floats freely without any external forces affecting it. This motion is the most basic motion of a rotating system, and is called inertial oscillation.