Detailed knowledge of asset performance typically resides with experienced operators because they interact with the asset continuously during real operating conditions. Plant engineers may understand design intent, calculations, specifications, and improvement projects. Maintenance technicians may understand maintainability, repair history, failure symptoms, and component condition. However, operators usually know how the asset behaves in production: normal sound, vibration, speed, temperature, process response, operating limits, minor abnormalities, product-quality changes, and early signs of degraded performance. That practical operating knowledge is extremely valuable in reliability improvement, operator-driven reliability, defect elimination, and work identification. In CRL’s Work Execution Management domain, reliability is not delivered by maintenance alone. Work execution depends on the integration of operations, maintenance, planning, supervision, and engineering. Experienced operators are often the first to detect abnormal conditions before formal condition-monitoring systems identify them. This is why mature reliability programs involve operators in basic care, inspection, early abnormality reporting, and standard work. The Uptime Elements CRL framework includes WEM as one of the five knowledge domains, confirming that disciplined work execution and operating involvement are part of reliability leadership competence.