Hanlon's razor
expressionops culture
The heuristic to never attribute to malice what is adequately explained by stupidity or mistake.
When something goes wrong, an honest error or oversight is usually more likely than a deliberate plot, and assuming malice poisons collaboration. In incident reviews it pairs naturally with blameless culture: look for the broken process, not the villain.
Never attribute to malice that which is adequately explained by stupidity, though incompetence is the kinder and usually more accurate word. The value is not charity for its own sake: most confusing behaviour really does come from someone being busy, under-informed, or working from a different set of facts.
In operations it is a debugging heuristic. The change that broke production was probably not reckless, it was probably made by someone who did not know about the dependency. The team that ignored your requirement probably never received it. Starting from that assumption produces better questions and faster resolution than starting from an accusation, and it costs nothing if you turn out to be wrong.
The limit matters and is often left off. In security, assuming incompetence is a failure mode: attackers deliberately construct activity that looks like error, and a razor applied to a genuine intrusion delays the response. The useful formulation is that Hanlon's razor is the right prior for colleagues and the wrong prior for adversaries, and knowing which situation you are in is the actual judgement.
Also known as: Hanlon's razor