Observability is no longer optional in cloud-native systems but "turn it on and hope" is not a strategy. OpenTelemetry autoinstrumentation promises instant visibility, yet in practice it can quietly introduce cost, performance, and security risks when used without intent.

This talk challenges the idea that more telemetry automatically means better observability. Using a real production example as context, we'll show how autoinstrumentation can surface far more internal behavior than teams expect, creating noise instead of insight. We'll examine what goes wrong, why defaults are dangerous, and how easily good intentions can backfire at scale.

We'll also be clear about the upside: when manual instrumentation isn't feasible, autoinstrumentation is still better than having no telemetry at all. The key is knowing where it helps, where it hurts, and how to use it deliberately.