Your Metric Is Not Your State
ken_walger·
Using a refractometer as a metaphor, the author illustrates why raw metrics can mislead developers about system health. Just as a refractometer reads sugar content that changes once fermentation begins, a metric like CPU usage or request latency can mask underlying state changes when new factors—such as background jobs or feature flags—are introduced. The piece urges engineers to treat observability data as a proxy, not a definitive state, and to combine quantitative readings with contextual knowledge to avoid false confidence in system performance.