Three buying patterns sort the choice cleanly.
Pick Grafana. Self-operated if you want full control and have the operations bandwidth; Grafana Cloud if you want managed but with the LGTM architecture preserved. Build your dashboards, write your alerting rules, own the stack.
If you want one vendor, deep capability, and budget isn’t a forcing function
Pick Datadog. Plan for the metered-dimension bill — every custom metric, every GB of log ingest, every APM-instrumented host bills independently. The capability is there; check the math before renewal time.
If you want managed-quality observability without managed-tier pricing dynamics
Pick Netdata. Single-binary install, per-second collection, ML on every metric, per-node pricing that doesn’t compound on cardinality. The honest gap is tracing (pair with Jaeger or Tempo until it ships) and APM depth — for infrastructure and logs, this is the path with the lowest cost-and-attention tax.
The recurring observation: Grafana-vs-Datadog is rarely a clear winner because both platforms solve the same problem with different cost models. Netdata isn’t a perfect fit for every workload — but for infrastructure-first teams, it’s the option that breaks the false dichotomy this comparison usually presents.