By: CLC Editorial Team
For years, retail media has been sold on its measurability. Every impression, click, and conversion could be tracked down to the SKU. Compared to the fuzzy world of TV or even parts of digital, retail media felt like the Holy Grail: put in X dollars, get back Y in sales, prove your ROAS.
But here’s the uncomfortable truth: last-click attribution doesn’t tell us if we’re actually driving growth.
Yes, clicks look good in a dashboard. But were those sales truly influenced by the ad — or would they have happened anyway because the shopper already had the brand in their basket? As retail media budgets scale into the billions, that question is no longer academic. It’s existential.
The industry is waking up to a new mantra: measure what matters. And that’s pushing brands, agencies, and retailers alike to evolve their attribution playbook.
Why Moving Beyond Clicks Matters
- Clicks don’t equal incrementality. A sponsored ad for Oreo may get clicked, but would the shopper have bought Oreos regardless? Without separating incremental sales from baseline sales, brands risk misallocating millions.
- Retail media costs are climbing. CPMs and CPCs are rising across every major RMN. When impressions are expensive, proving incremental lift becomes table stakes.
- Retailers need to compete with the Big 3. To win brand budgets away from Meta, Google, and Amazon, RMNs have to demonstrate they can drive new growth, not just shuffle share.
In short: measuring clicks is easy. Measuring incrementality is harder — but infinitely more valuable.
The Evolving Measurement Toolkit
So what’s replacing “clicks + ROAS” as the gold standard? Three tools are rising to the top.
1. Incrementality Testing
- Uses exposed vs. holdout groups to determine the true lift of an ad campaign.
- Answers the most important question: Did this ad drive sales we wouldn’t have gotten otherwise?
- Example: A cereal brand tests onsite display during back-to-school. Results show 40% of attributed sales came from loyalists, but 60% was incremental lift — real growth.
- Pitfall: Can be costly, requires careful design, and isn’t always scalable during key tentpoles.
2. Marketing Mix Modeling (MMM)
- A statistical model that looks at sales across all channels — retail media, TV, social, search — and assigns credit over time.
- Helps brands understand how retail media works in context, not in a silo.
- Example: MMM reveals that retail media is most effective when layered with national TV, driving double-digit lift compared to running either in isolation.
- Pitfall: Often slow, requires significant data quality, and may feel too “zoomed out” for tactical campaign decisions.
3. Retailer Clean Rooms
- Secure, privacy-safe environments where retailers and brands can match first-party data.
- Enables shopper-level insights: path to purchase, overlap between online/offline behavior, cross-channel exposure.
- Example: A clean room analysis shows that a shopper who saw a snack ad on Instagram and later on a retailer’s site was 3x more likely to purchase — proving retail media’s multiplier effect.
- Pitfall: Every retailer seems to have their own clean room with different rules and tech. Brands face steep learning curves and interoperability headaches.
Common Pitfalls to Avoid
Even with advanced tools, brands often stumble:
- Over-attribution: Counting every exposed shopper as influenced by the ad — inflating ROAS beyond reality.
- Ignoring the baseline: Forgetting that loyal customers will buy with or without media.
- Shiny object syndrome: Chasing incrementality tests one week, clean rooms the next, without building a consistent, scalable framework.
The Road Ahead
Attribution in retail media is moving from “What happened?” to “What mattered?”
The brands who win will:
- Use incrementality tests to prove lift.
- Layer in MMM to understand the full marketing mix.
- Leverage clean rooms for granular, shopper-level insights.
This shift won’t be easy. It requires better data, tighter brand-retailer collaboration, and often a cultural change in how organizations view measurement. But the payoff is huge: media strategies that actually grow the pie, not just rearrange it.
Because at the end of the day, clicks are cheap. Incrementality is priceless.