The present invention differentiates between systematic and non-systematic conditions by observing a figure of merit over a series of many observation events. An arrangement comprising a screw and a thread-armoring element immobilized on it for carrying out said method is also described. The lock assembly includes a key module rotated by a key member, wherein the key module being positioned in the handle portion, a rotary shaft rotated by a rotation of the key module and locking or unlocking the door through a dead lock member, and a rotation transmitter for transmitting the rotation of the key module to the rotary shaft.