With offices in the UK, US, Canada, Australia, and South Korea, global commerce marketing practice Mars United Commerce works with some of the biggest names in retail, including Lego and Unilever. In September last year, Mars was acquired by Publicis Groupe for an undisclosed fee.
New Digital Age recently spoke with Katrina Smart, VP Digital Commerce at Mars United Commerce. Smart believes that the marketing industry needs to turn its back on ROAS (Return On Ad Spend) as the key metric of success, particularly in light of the growth of retail media.
Why do you think that the marketing industry needs to move beyond ROAS as a metric?
ROAS is so 2024! While it’s been a valuable metric for understanding short-term retail media effectiveness, it’s inherently limited. It was born out of a search-driven, keyword-focused landscape, where immediate return on ad spend was the primary concern. Today, though, retail media has evolved. The conversation needs to shift toward broader, more meaningful performance indicators—like incrementality, customer lifetime value, and new-to-brand acquisition. If we’re only optimising for ROAS, we’re missing the bigger picture of sustainable brand growth.
Why is ROAS problematic in the context of Retail Media measurement?
Retail media networks continue to report on ROAS as a core metric, but brands that want to stay ahead must look beyond it. Expanding measurement capabilities is crucial. We should be tracking share of voice, customer retention, and most importantly, incrementality – understanding not just what media has sold, but how much of that impact was truly incremental.
The future of retail media measurement will focus on answering deeper questions: Are we reaching new customers? Are we increasing our overall market share? Are we converting shoppers who weren’t previously engaging with our brand? That’s where the real value lies.
The real challenge today is connecting the total commerce journey. Retail media is just one piece of the puzzle—it needs to work seamlessly alongside other channels to create a unified consumer experience. It’s not just about securing placements within a retailer’s ecosystem; it’s about ensuring that messaging is cohesive across social commerce, direct-to-consumer channels, in-store activations, and even traditional advertising.
For instance, a campaign that starts with a TikTok ad should flow naturally into the ecommerce experience and ultimately translate to in-store engagement. Consumers don’t think in silos, so neither should our strategies.
Are modern marketers struggling with the pace of change?
The pace of change in retail media is relentless. Every week, new platforms and capabilities are emerging. Just a couple of weeks ago, Ocado Ads introduced its off-site proposition, Audience Plus, demonstrating how quickly retailers are innovating. That’s why a big part of my role is staying ahead of industry trends – understanding new opportunities as they arise and ensuring that our teams and clients can act on them effectively. If brands want to succeed in this space, they need to be agile, continuously testing, learning, and adapting to this rapidly shifting landscape.
What are your business priorities for the year ahead?
Our top priorities this year center around improving measurement. We’re focused on advancing our understanding of key performance indicators beyond traditional metrics, ensuring we have a holistic view of performance across retailers.
One of the biggest opportunities is commerce media mix modeling, which helps us bridge the gap between digital commerce and traditional media. Instead of looking at retail media in isolation, we’re analyzing how it fits into the broader marketing mix – how retail investments complement TV, out-of-home, and social advertising.
Additionally, incrementality remains a top focus. Not every retail media network provides robust incrementality measurement yet, but for those that do, we’re all in – testing, learning, and applying those insights to drive better results. And for the platforms that don’t? We see it as an opportunity to collaborate and push for more advanced measurement solutions across the industry.
