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Foundations

The inspection pyramid

A defect travels through a long chain before it becomes a decision. The later you catch a problem, the more it costs.

Hover a layer A defect travels down this chain before it becomes a decision. Each step can hide or destroy information - and the further down you discover a problem, the more it costs to fix.
The cost of discovering a problem grows as you move down the chain.

Most people picture inspection as a short, clean path:

Defect -> Camera -> Detection

Reality is a much longer chain, and every link can hide or destroy information. The diagram above is interactive: hover or tap any layer to see what goes wrong there and why it gets more expensive the further down you discover it.

Why the chain matters

A defect has to survive physics, lighting, optics, motion, the camera, the software, the operator, and finally a business decision before anyone acts on it. If the information is lost early (bad lighting, wrong optic) no amount of clever software downstream can recover it.

The expensive direction

The further down the chain you discover a problem, the more it costs to fix:

  • Catch it at lighting: change a light, cost is minutes.
  • Catch it at software: re-tune algorithms, cost is days.
  • Catch it at production: false calls and escapes, cost is reputation and money.

How I use it

When a system underperforms, I walk the pyramid top-down and ask: *is the information even present in the image?* Most of the time the answer reveals that the problem is far higher up the chain than where people were looking.