Six months after deployment, the CFO asks: 'What has this model actually earned us?' How do you answer?
Accuracy metrics don't survive contact with a CFO. The holdout pattern that turns a model into a permanent revenue receipt, and what to do when nobody set one up six months ago.
Updated Aug 2026 · Grounded in real Forward Deployed Engineer interview loops and written to a senior-engineer editorial bar.
Accuracy metrics don't survive contact with a CFO. The holdout pattern that turns a model into a permanent revenue receipt, and what to do when nobody set one up six months ago.
Lead with where the obvious approach breaks, because that is the judgment they are screening for — most candidates jump straight to the happy path and lose the room.
Then walk the failure back through the pipeline in order, naming the one metric the customer's exec sponsor actually cares about before you propose the fix.
