Latest / The CMO Podcast with Fexingo: Marketing Leadership, Budgets, and Executive Strategy / The Conversion Rate Lie That Wasteful CMOs Believe
Transcript
- Lucas: So there is this metric that I think has become almost a religion in marketing, and it is conversion rate. Specifically, conversion rate as the single most important KPI on the dashboard. Luna: And you think that's a problem? Lucas: I think it's actually dangerous. Because what most marketers are measuring when they say 'conversion rate' is not what they think it is. They are measuring last-click attribution, which inflates the number by, in some cases, 300 percent. Luna: Three hundred percent? That's not a rounding error. That's a completely different number. Lucas: Exactly. And it leads to bad decisions. Let me give you a concrete example. There was a DTC mattress startup — I won't name them because the story is from a consultant who worked there under NDA — but they were spending heavily on Facebook ads. Their conversion rate from click to purchase was about 4.5 percent, which in e-commerce is considered pretty good. The CMO was thrilled. But when they switched to a blended attribution model — one that accounts for all touchpoints across the customer journey — that conversion rate dropped to 1.2 percent. Luna: So overnight, their 'good' performance became mediocre. And the CMO had to explain to the board why their numbers were suddenly worse. Lucas: Right. But here is the kicker — the business was actually fine. The blended number was more accurate. The problem was they had been optimizing for a false positive. They were doubling down on the last click, ignoring all the brand-building touchpoints that happened earlier. Luna: So they were basically training their algorithm to chase the easy conversion, not the valuable customer. Lucas: And that's exactly what a Wharton study from earlier this year found. The Marketing Analytics Center there looked at 50 brands over two years. The ones that optimized solely for conversion rate saw 40 percent lower customer lifetime value than the ones using a blended model. Luna: Forty percent lower LTV. That is not marginal. That is a structural business problem. Lucas: And here is where it gets really interesting for anyone running a marketing budget right now. The privacy changes — the deprecation of third-party cookies, Apple's Mail Privacy Protection, all of that — they are making last-click attribution even less reliable. So if your dashboard is built on that foundation, you are flying blind. Luna: So what is the alternative? I know a lot of CMOs are moving to media mix modeling, but that has its own issues. Lucas: Yeah, media mix modeling is great for the big picture — understanding which channels drove sales at an aggregate level — but it is terrible for real-time optimization. It's like using a rearview mirror while driving. You need both: blended attribution for understanding the customer journey, and media mix modeling for strategic allocation. Luna: But that requires a lot of data integration. Most marketing teams don't have the infrastructure for that. Lucas: That is the real barrier. And it is why so many companies default to the simple, wrong number. But I think there is a middle ground. Some companies are using 'incremental conversion rate' — basically running controlled experiments to see if the ad actually caused the sale, versus the sale happening anyway. Luna: That sounds expensive and slow. Lucas: It is. But it is better than optimizing for a number that is 300 percent too high. And honestly, if these marketing conversations have sparked something you've actually used — a new attribution model, a different way of thinking about LTV — then that's the link. Buy me a coffee dot com slash fexingo. It literally costs less than a latte, and it's what keeps this show ad-free and independent. Luna: Yeah, I second that. We don't do sponsors, we don't do ads, we just do the research. And listener support makes that possible. Lucas: So back to the conversion rate lie. The reason I think this matters right now — May 2026 — is that the cost of acquiring customers through performance channels has gone up about 25 percent year-over-year. So every wasted dollar hurts more. Luna: And if you are overvaluing conversions that are really just cannibalizing organic sales, you are burning cash on a fake signal. Lucas: Exactly. There is a famous example from the early days of Casper. They were spending millions on paid search for 'mattress reviews' — a term that had a high conversion rate. But when they ran an incrementality test, they found that 70 percent of those conversions would have happened anyway through organic search. Luna: So they were paying for sales they would have gotten for free. Lucas: Exactly. And they didn't catch it because their attribution model credited the last click — which was the paid ad — not the organic search that actually brought the customer in the first time. Luna: So what is the fix? How do CMOs break the addiction to last-click? Lucas: First, stop using last-click as your primary optimization metric. Use it as a directional signal, not a truth. Second, invest in a good data clean room or a CDP that can actually track the customer journey across devices and platforms. Third, run incrementality tests on your top three campaigns every quarter. Luna: That is a lot of work. Especially for smaller marketing teams. Lucas: It is. But the cost of not doing it is higher. Because if you are optimizing for a number that is 300 percent inflated, you are not just wasting money — you are building a strategy on a lie. And that lie will catch up with you when the board asks why LTV is dropping. Luna: So the real question is: do you want to be the CMO who had great conversion rates and a failing business, or the one who had mediocre conversion rates and a healthy LTV? Lucas: That is exactly the choice. And I think the smart CMOs are already making the shift. Wayfair, for example, has been public about moving to a blended attribution model. They say it reduced their reported conversion rate by about 40 percent, but their actual revenue per customer went up. Luna: Because they stopped chasing the cheap conversions and started investing in the customer journey. Lucas: Right. And that is the kind of thinking that builds durable brands, not just quarterly wins. So as we head into the summer, if you are a CMO or a marketing leader, take a hard look at your dashboard. Ask yourself: what am I actually optimizing for? If the answer is 'conversion rate,' you might have a problem. Luna: And if you want to dig deeper, we will link to the Wharton study in the show notes. Lucas: Yeah, we will. And as always, thanks for being curious.