The costsRecently formalised
Rework externality
externalité de reprise
The cost is displaced from the immediate user onto downstream recipients: reviewers, managers, clients, colleagues, administrative staff. The person who gains the time is not the person who loses it.
Most recent measurement: close to 40% of AI time savings are lost again to rework, meaning error correction, rewriting and verification.
What it means for an SME running AI
An AI project can show a real productivity gain at every individual step and still produce nothing at the level of the company. That is not a paradox, it is an accounting boundary.
Sources
- Cheung, Cambridge Open Engage, mai 2026, pour le mécanisme
- Workday, janvier 2026, pour la mesure
Related terms
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