Attribution answered a question the industry has stopped asking. The question that decides budgets — did the spend cause the revenue — needs different instruments, and a different referee.
Attribution was built for a web that no longer exists: one person, one device, a trackable click-path from ad to checkout. Privacy enforcement broke the path. Walled gardens closed over it. And now AI assistants answer, compare, and recommend before a site is ever visited — the most important touch in the journey increasingly leaves no touch at all.
What remains is a reporting layer in which every platform grades its own homework. Add the conversions each one claims and you get a number comfortably larger than revenue. Everyone in the room knows it; the numbers still run the meeting.
Add up the conversions each platform claims and you get a number larger than revenue. Everyone knows it. The numbers still run the meeting.
The instruments that survive finance review
Incrementality is the standard. Geo-lift tests and audience holdouts measure the only thing a CFO should fund: revenue that would not have arrived otherwise. They are slower than a dashboard and they are the truth — proof scales with the spend at stake, so the biggest lines get the strongest designs.
Where experiments cannot reach — long cycles, small cells, brand effects — media mix models rebuilt with modern inference carry the allocation question. A model is a hypothesis, so it is calibrated against the experiments, and retired when it stops predicting.
And beneath both sits the referee: the ledger. Spend, revenue, cost, and margin reconciled to the bank on a cadence both marketing and finance sign. Definitions frozen in writing — CAC, margin, payback — so nobody moves the goalposts, including the operator.
Measurement is a governance function
The operational consequence is larger than the technical one. When measurement reconciles to the bank, budgets can carry kill criteria from the day they are approved. What proves out scales; what stops paying is retired — automations included. Measurement stops being the report that arrives after the money is spent and becomes the gate the money passes through.
That is the design principle we build on: experiments where you can, models where you must, the ledger always. The stack owns the counting; the operator owns the call.
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