artifacts

Availability, reproducibility and a supply chain you can answer questions about. The build that worked yesterday and fails today because an upstream package moved is the argument, and it costs a day every time.

Follow scheduling eligibility, job isolation and artifact transfer, then diagnose a queued job whose available runners cannot satisfy its requirements.

Build once and move the same bytes. The moment an environment rebuilds from source, you are testing something that has never run anywhere, and no amount of pipeline output can tell you what production holds.