When a team writes "this integration will cost X to maintain," that sentence hides a chain of choices. Someone chose which work counts as maintenance, which vendors were assumed, how often the model or API would change, and how many hours a person would spend fixing things. Each of those is a decision, and each can be wrong later.
Cost estimators already argue that AI cost structures cannot be treated as a single point estimate. Because AI systems have usage-driven costs that keep evolving after deployment, and because models degrade as real-world data shifts, honest estimates are presented as a range with defined assumptions rather than one fixed figure (itsvalue.com). That is the core argument for the record: if the estimate is a range built on assumptions, the assumptions are the thing a reviewer must inspect.
There is a second reason. Integration cost breakdowns show that initial development often accounts for only 30 to 40 percent of the total cost of ownership, with maintenance consuming the rest (Exalate). A maintenance estimate is therefore usually the larger financial decision in the room. Spending the effort on a record for the bigger number is not bureaucracy.
A useful framing comes from teams that practice source-backed decision making. They tie every recommendation, assumption and tradeoff to identifiable evidence so a reviewer can verify the logic and reproduce the outcome later, and they label each claim as a fact, a calculation or an assumption when it is captured (The Intent Ledger). That is exactly the discipline a maintenance estimate needs.



