The Stable Liar Every metric you optimise quietly stops measuring what you meant. The dangerous ones never break. They keep reporting green while the thing underneath rots. Proof & Trust 2026·06·02 · 11 min The stable liar
This is the stable liar: a number that goes on looking right long after it stopped being right. It is a structural property of measurement under pressure, and it has a law underneath it.
Published 2 June 2026 in The Stable Liar
01 · Introduced in
2 Jun 2026
The Stable Liar Every metric you optimise quietly stops measuring what you meant. The dangerous ones never break. They keep reporting green while the thing underneath rots. Proof & Trust 2026·06·02 · 11 min 02 · Also in
2 pieces
Every other piece whose text uses the term, oldest first, with the sentence where it first does. The list is read from the essays each time the site is built.
- WalkthroughsNever Let Claude Code Tell You It's Done
“If you want the why under this: How Reliable Is Your AI Agent makes the broader case, and The Stable Liar is this exact failure mode up close.”
8 min
- WalkthroughsYour Tests Pass. So What?
“Related: How Reliable Is Your AI Agent makes the broader case, The Stable Liar shows the failure mode up close, and Never Let Claude Code Tell You It's Done builds the test gate this piece audits.”
19 min
03 · Run it on your own work
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