Every Major Retail Media Network Can Prove Incrementality — And That's the Problem
Five years ago, the hardest question in retail media was whether the ads worked at all.
Today, every major retail media network can hand a brand an incrementality read. That should feel like a finish line. For most brands, it feels like noise.
I spent eight years inside one of retail media's original measurement engines, building the kind of lift studies that turn media spend into a business case. The discipline has come a long way since then.
But the progress we fought for has created a problem almost no one anticipated.
Attribution Was the Easy Part
In retail media's first chapter, measurement meant attribution. Did a shopper see the ad, then buy the product? Closed-loop attribution answered that question, and it was enough to unlock the first wave of budgets.
Then expectations matured. Buyers stopped asking whether a sale followed an ad and started asking the harder question: Would that sale have happened anyway?
Incrementality became the standard. Attribution tells you what happened. Incrementality tells you what you caused. The gap between those two is where real budget decisions are made.
Then Everyone Built Their Own Version
As incrementality became table stakes, every major network raced to build it. The long tail still trades in attribution. But among the networks large enough to command real budget, lift is now the price of entry.
Each one designed its own approach: Different test-and-control logic, different baselines and different definitions of what even counts as "incremental."
Recent industry research makes the stakes concrete. Albertsons Media Collective, working with professors from Northwestern's Kellogg School, took a fixed set of campaigns and changed only the measurement methodology. The results showed that iROAS moved by as much as 6.5x. In 83% of campaigns, the result flipped between positive and negative. Same campaigns, same sales — but different math.
The study changed one variable on purpose. In the market, methodology is exactly the variable that differs from network to network. So a brand comparing one network's iROAS to another's may be reading a gap that reflects methodology, not media.
The Cost Isn't Measurement — It's Comparability
This is the quiet tax on retail media's success. The bottleneck is no longer whether incrementality can be measured. It is whether the results can be compared.
Brands cannot allocate a portfolio against numbers that do not share a denominator. When a network is both the seller of the media and the scorekeeper of its performance, brands are left to reconcile results that were never built to line up.
The instinct is to trust the highest number, which can reward the most generous methodology rather than the most effective media.
Standards Help — They Do Not Solve It
The industry's reflex is to fix this with standards, and that work matters. The IAB has done genuinely valuable work defining incrementality and pushing networks to disclose how they measure. Standards, however, have a ceiling.
Even a well-applied standard leaves room for interpretation, and implementation varies from one network to the next. Documenting how each number was built does not make two numbers built differently comparable.
Transparency tells a brand how a result was produced. It does not put every result on the same scale.
What closes that gap is a much harder question. It likely takes a shared way of reading results across networks, one method applied consistently to each, so comparisons are made on equal terms.
No single approach is flawless. Each carries methodological choices of its own. But that is the tradeoff worth working through. Without it, more measurement will not buy brands more clarity. It will buy them more confusion, deeper distrust and a slow erosion of confidence in the one metric retail media's growth was built on.
Incrementality proved retail media works. Comparability is what will earn it the next wave of investment. That is the opportunity the next five years should unlock.
About the Author
Moody Khan is VP of RMN measurement strategy at Circana. Prior to Circana, he spent eight years building and consulting on incrementality measurement at Kroger Precision Marketing, partnering with leading CPG advertisers.
