Maintenance Drag Ratio

Maintenance Drag Ratio is the share of an automation retainer consumed by keeping existing bots alive rather than building new ones. UI-level automation breaks when a target application changes a field label, a login flow, or a page layout, and that breakage lands on the agency as unbilled rework. The ratio matters because a bot that took 40 hours to build can quietly absorb 6 to 10 hours a month in selector fixes, and at a $150 blended rate that is $900 to $1,500 of margin gone before any new scope is sold. Prompt-driven tools shift the curve: BrowserAct rebuilds scrapers from a natural language description when a site changes, so drift costs a re-prompt instead of a developer afternoon. Track the ratio per client and reprice or migrate any account where upkeep crosses roughly a third of retainer hours.