Diagnosis skips the trivial cause because it is beneath the diagnostician's dignity to check it.
The failure is social rather than logical. An expert asked to investigate a problem begins at the level of their expertise, and checking whether the device is switched on implies the questioner might be a fool. The cost is borne by the hours spent on sophisticated hypotheses before someone junior enough to be unembarrassed looks at the cable.
In practice
- An escalated fault resolved by a restart was escalated past three people who would have felt foolish suggesting it.
- A consultant's report identifies a strategic misalignment in a company whose invoices go to the wrong address.
- Standing
- Compare Sutton's law and Occam's razor, which prescribe checking the likely and the simple first.
- Subject
- Decision-making & Reasoning
- Essay
- Paradoxes that broke theories, and sayings that outlived them