Stability is one of the important indicators for measuring lock performance. In this respect, mechanical locks are generally considered to have an advantage. The operation of a mechanical lock depends entirely on its mechanical structure and is not affected by batteries, circuits, or software systems.

A mechanical door lock is a door lock device that relies entirely on a mechanical structure to achieve its opening and locking functions. Its operation does not depend on electricity, batteries, or electronic control systems. The key drives the internal mechanical structure of the lock cylinder.