Your eval dashboard has 30 metrics. When one "moves," that is usually arithmetic, not a regression.

Here is the ritual. You ship a prompt change, rerun the eval suite, and open the dashboard. Thirty numbers sit there: faithfulness, answer relevance, context precision, toxicity, latency-adjusted quality, and two dozen more. Twenty-nine are flat. One dropped from 0.86 to 0.81 and the cell is red. Someone says "we regressed on groundedness," and the next hour goes to explaining a number that never needed explaining. I want to make the boring case that most of these red cells are not findings.…