Treat testability, observability, and recoverability as first-class design concerns, not afterthoughts. A system that cannot be easily tested, understood in production, or quickly restored is inherently low-quality. Build in the necessary instrumentation, APIs, and deployment mechanisms from the start.
Example
During the design phase for a new service, we must explicitly define how it will be observed via metrics and distributed tracing. The design is not considered complete until these aspects are addressed.
