Kubernetes: Orchestration as a Set of Control Loops

Kubernetes looks like a pile of object types until you notice it is one idea repeated. Store a description of the desired state, and run loops that compare it to reality and act on the difference. Because those loops read the current state rather than react to events, missed and duplicated messages are harmless and an interrupted controller simply resumes. This path builds the loop, shows every object as a controller joined by label matching, covers the two resource numbers that drive most cost and latency bugs, and ends with the failures the design itself creates.