Your CMO is presenting to the board using data produced by a measurement system they built or inherited and have a professional interest in defending. Your board is making governance decisions on the basis of that presentation. That is a circular information structure and it is producing governance risk that nobody in the room is naming.
The board's role is to provide oversight of the executive team's commercial judgements. That oversight requires information that is independent of the executive team's commercial interests. In the case of CMO performance and marketing investment return, the information the board receives is produced by the CMO's function, interpreted by the CMO's analysis, and presented through the CMO's narrative.
There is no independent read of the commercial system in that information flow. The board is governing from inside the perspective of the person being governed. That is not a criticism of the individual. It is a structural observation about the information architecture of the CMO-to-board relationship.
The board that wants genuine commercial governance over marketing investment needs an independent view of the commercial system that sits outside the CMO's information architecture. Not an audit. A senior, experienced commercial read that tells the board what the system is actually producing rather than what the function that operates it is reporting.
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