Sigma level — Sigma level represents how capable a process is at producing defect-free output.

In plain English

Sigma level shows how often things go wrong.

Higher sigma = fewer defects.
Lower sigma = more firefighting.

What they actually mean

Sigma levels look impressive in slides.

But a high sigma on the wrong metric is still meaningless.

If customers don’t feel the improvement, the sigma number doesn’t matter.

Example

Does it actually matter?

✅ Sometimes.
⚠️Sigma level is a signal — not a guarantee of value