<p>Because the change travels through people, not through the record. Someone updates the model, mentions it in a call, and the news reaches the foreman a week later, if at all.</p> <p>The effect is rework. The crew builds from the old version and the fix costs more than the change would have. A clash caught in the model costs about $50. The same clash found in the field costs $5,000 to $50,000.</p> <p>You can shorten the path:</p> <ul><li>Publish after the change so it becomes a versioned snapshot with its author and milestone.</li><li>Compare it to the previous revision. It shows what moved, element by element.</li><li>Pin an issue to each element that affects work underway and tag the owner.</li><li>Let the 6am digest carry the issue to them the next morning.</li></ul> <p>The comparison takes about 15 minutes instead of a 90-minute meeting. And a change that is flagged on day one does not become a change order on day thirty.</p>