ML systems rarely fail loudly - they decay over weeks while dashboards still look green. Observability supplies the diagnostic depth to catch drift, data skew, and silent accuracy loss before business metrics move.
A recommender can serve low-latency responses with zero HTTP errors while ranking quality craters. Infrastructure-only telemetry misses that class of failure - you need ML-native signals stitched across ingestion, features, inference, and feedback.
Go beyond basic monitoring with the full practice checklist in our MLOps best practices guide.

Combine Prometheus-class metric stores, specialised drift monitors, and composite dashboards rather than swapping your entire platform every vendor cycle.
Observability must span from ingestion through feedback to be effective.
Input drift shifts feature statistics while labels lag; concept drift shifts the mapping from inputs to correctness.
Decide thresholds (for example PSI > 0.2) and remediation trees before paging someone at 02:00.
Metrics store + structured logging backbone + traces feeding a central dashboard - augment what you already operate instead of ripping observability sideways.
Monitoring tracks known metrics and fires threshold alerts. Observability layers metrics, structured logs, and traces so engineers can interrogate unknown failure modes - answering why behaviour shifted, not merely that an alert fired.
Typical stacks combine Prometheus-compatible metrics sinks, drift-focused monitors like Evidently, OpenTelemetry for traces, MLflow lineage for experimentation, plus Grafana - pragmatic teams mix best-of-breed rather than monoculture consoles.
Track input distributions versus training baselines (PSI, KS, KL divergence) while parallel paths confirm concept drift with arriving labels - without labels you sense shifts in statistics and calibrated confidence behaviour, yet cannot prove accuracy loss alone.
When pre-agreed statistical or business KPI breaches occur - e.g. PSI alarms, calibrated accuracy regressions against labelled holds, backlog volumes overwhelming reviewers - plus runbooks authored before dashboards wake people at midnight.
Serving latency can look green while accuracy collapses silently when upstream features skew. Observability attaches ML-native signals spanning ingestion through feedback capture, complementing uptime-focused tooling.
Brainpool maps where your ML telemetry stops short, which lifecycle stages lack signal, and how to extend your existing Prometheus, OpenTelemetry, and experiment tooling without another rip-and-replace.