Metrics are commonly used to assess effectiveness. Impressions, screen uptime, and content schedules support system monitoring. In practice, human response shapes outcomes. Content can be playing, still be ignored. Understanding this gap supports better planning. when content fits attention patterns. Limits of data-driven evaluation Logs confirm delivery. It supports maintenance. https://andrewoperationsnotes.onesmablog.com/observations-on-digital-signage-across-different-work-environments-80761232