Can confirm that in my former life as a Chief Pilot, almost weekly I got a 'please explain' via an incident report because pilots set the wrong code. I was expected to fill in forms in quadruplicate with sh!t like 'root cause' and 'remedial action' blah blah. Eventually I got so p!ssed off with this waste of time that I would offer the cause as ' human error' or occasionally tongue-in- cheek (in the case of repeated offenders, who also p!ssed me off)) as 'pilot suspected to be dyslexic - suggest you refer to the Director of Aviation Medicine' and the fix as ''impossible to eliminate until the species is extinct". Or in the case of the suspected dyslexic "awaiting medical breakthrough". It seemed to satisfy them because they never got back, or if they did I binned it. If they did go after the repeat offenders, that would have been sweet, too. But they never did. ****wits.....