A period with no recorded complaints can be encouraging, but the record depends on what was delivered and how feedback could reach the team. It is not a complete inspection of every item in use.
ASQ describes continuous improvement as ongoing work informed by products, services and processes. ASQ — continuous improvement.
Keep the population visible
For a character range, identify the relevant deliveries and observation period before comparing complaint counts. A newly launched item has a different exposure history from an older range.
Review the information route
Consider whether feedback is captured consistently across channels. Do not invent a defect rate from missing reports. Use the available evidence to plan further review while keeping actual findings separate from assumptions about unobserved use.
Source reviewed 25 October 2026. Interpretation and original diagrams: PLUSHIP / Qunhe. Examples are illustrative.
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