The cost of leaving AI traffic out of ROAS
When a channel goes uncounted, its revenue is credited to whatever sat closest to the sale. That inflates the neighbours and distorts every budget decision built on them.
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By Joris van Huët, Founder & CEOUpdated 2 min read
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An uncounted channel does not cost you its own revenue. It costs you the accuracy of every channel that absorbs it.
The mechanism
Revenue does not disappear when a channel is invisible. It is credited to whatever was closest to the sale: branded search, email, direct. Those channels now look better than they are.
You then scale them, because the numbers say to. The scaling underperforms, because the borrowed revenue does not scale with the spend that never caused it.
What it costs, concretely
| Effect | Where it lands |
|---|---|
| Overstated ROAS on the absorbing channel | Budget moves toward it |
| Understated contribution from the real source | That work looks unjustified and gets cut |
| Diminishing returns misread as fatigue | Creative gets blamed for an attribution artefact |
| Forecasts built on the inflated figure | Miss, with no obvious cause |
The third row is the expensive one. A team that concludes its ads are fatiguing will rebuild creative, which is slow and costly, when the actual problem is that a different channel's revenue stopped flowing into the number.
Why this one compounds
Ordinary measurement error is noise around a true value. This is a systematic transfer: the same channels are credited every month, so the error grows in one direction and the budget follows it.
That is the difference between a number being imprecise and a number being biased, and only the second one steers you.
The correction that does not require solving it
You do not need an exact figure for assistant traffic to stop the damage. You need the absorbing channels to carry a caveat.
Mark branded search, direct and email as containing an unknown share of demand created elsewhere. Then require a causal read before scaling any of them, rather than a reported ROAS.
Related answers
Frequently asked questions
What does an uncounted channel actually cost?
Not its own revenue, which still arrives, but the accuracy of every channel that absorbs it. Branded search, direct and email look better than they are, budget moves toward them, and the scaling underperforms.Why is this worse than ordinary measurement error?
Ordinary error is noise around a true value. This is a systematic transfer in one direction, month after month, so the bias accumulates and the budget follows it.Can I fix this without measuring AI traffic exactly?
Yes. Mark the absorbing channels as containing an unknown share of demand created elsewhere, and require a causal read before scaling any of them rather than acting on reported ROAS.
Go deeper: Incrementality testing, explained.
Sixty-second versions of these ideas: Causality Engine on YouTube Shorts.
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Terms in this article
- AttributionAttribution identifies user actions that contribute to a desired outcome and assigns value to each. It reveals which marketing touchpoints drive conversions.
- Attribution ReportAttribution Report shows which touchpoints or channels receive credit for a conversion. It identifies which campaigns drive desired actions.
- ReturnsEcommerce returns, or reverse logistics, is the process of customers sending back purchased items to the retailer. Causal analysis helps improve products and reduce return rates.
- RevenueRevenue is the total income generated by the sale of goods or services related to a company's primary operations.
- ROASROAS: Return on Ad Spend measures the revenue generated for each dollar spent on advertising. Causal attribution calculates an accurate ROAS by showing the true impact of ad campaigns.