They were sure their attribution was solid. It was hiding 34%.

Kentekenverslag gives people about to buy a second-hand car the full story behind the number plate: damage history, odometer fraud, theft checks, APK records, previous owners and import risk, delivered as an instant PDF report. More than 500,000 Dutch buyers have used it, and it carries a 4.5 out of 5 rating on Trustpilot.

The business runs on paid acquisition. High-intent searches and social campaigns on Google and Meta drive buyers to a single, low-priced report purchase. Volume is high, the ticket is small, and the whole model only works if the cost per report stays below what each report earns. By every platform dashboard, it did, comfortably.

On a low-ticket, high-volume product, precision is everything. A reported ROAS that is off by even a fraction sends the bidding algorithms chasing the wrong campaigns thousands of times a day. And platform numbers are built to be off: Google counts what Google can see, Meta counts what Meta can see, and the same report purchase often gets claimed twice.

On a Dutch consumer site, consent makes it worse. A large share of purchases fire before the cookie banner is answered, or from visitors who decline tracking, so those conversions never make it back to the platforms at all. The team suspected their payment provider and their ad dashboards were telling two different stories, but they had no independent number to prove it.

Motiv captured every report purchase server-side, straight from Kentekenverslag’s own transactions, and calculated one verified ROAS independently of any ad platform. Each conversion was classified by the consent attached to it: Observed purchases were dispatched back to the platforms, Restricted ones were recorded but never sent.

For the first time the team could put what the platforms claimed next to what actually happened at checkout. The difference, shown in euros per channel, was the Attribution Gap they had been carrying without knowing it.

Once the real numbers were on the table, the account reshuffled. Campaigns that looked efficient on inflated, double-counted data were quietly losing money on a few-euro product. Campaigns that genuinely produced profitable report sales had been underfunded. The team moved spend toward what actually worked.

In the first 90 days, Kentekenverslag recovered €47,000 of Attribution Gap value, and just as importantly, they finally knew which euro of spend was real and which was a reporting artefact.

The team stopped treating the platform dashboard as the source of truth. Verified ROAS from Motiv became the number they plan against, and the Attribution Gap is now a line they watch every month rather than a blind spot they carry.

Nothing about their channels or budget changed overnight. What changed was the quality of the data underneath every decision, and with clean, consent-checked signal going back to the platforms, the algorithms finally optimise toward real, profitable report sales.