Ditch Cost Per Conversion: Measure This Instead

For businesses aiming to maximize their advertising impact, focusing solely on cost per conversion can inadvertently limit growth and leave valuable opportunities untouched. While keeping an eye on spending efficiency is wise, making it the primary goal often results in campaigns that fail to reach their full potential. The real objective of any marketing effort is to generate a specific volume of leads, sales, or calls, not just to acquire them at the lowest possible price.

A Key Performance Indicator, or KPI, serves as the definitive measure of a campaign’s success. It’s the central figure that determines whether your efforts have paid off. Even if secondary metrics fall short, a strong performance in your KPI means the campaign is on the right track. Reflect on your last initiative: was the true aim to secure the cheapest conversions, or was it to achieve a necessary number of them? The fundamental goal is almost always about securing a required volume of conversions, with cost being an important, but secondary, consideration.

Efficiency metrics can be misleading. Picture yourself as the owner of an apple orchard. If you hire someone to pick apples and judge their performance based on the time taken to collect just one, they would naturally choose the easiest apple within reach. Using that single data point to estimate the time needed for the entire harvest would give a wildly inaccurate picture. Similarly, if you requested one hundred apples, the picker would gather the most accessible ones first. The average time per apple would seem low, but it wouldn’t reflect the effort required to harvest the entire orchard.

An orchard manager focused purely on minimizing the cost per apple would simply pick the single easiest apple and stop. This approach, while efficient on paper, leaves the vast majority of the crop, and potential profit, unharvested. Advertising platforms operate on a similar principle; when tasked with maximizing conversions for a fixed budget, they will first target the consumers who are easiest to convert. As you increase the budget, the platform continues to find conversions, but the cost for each additional one tends to rise.

A more effective strategy is to establish conversion volume as your primary KPI. You need a certain number of leads or sales for a campaign to be deemed successful. Treat cost per conversion as a regulatory tool and a source of insight. Begin by calculating the maximum cost per conversion that your business can sustain while remaining profitable. Use this figure as a cap for your campaign spending. Then, conduct tests to understand how increasing your budget affects efficiency, aiming to operate just below your profitability threshold. This method allows you to capture the maximum number of conversions without sacrificing financial health.

This logic also applies to Return on Ad Spend (ROAS). It’s tempting to chase the highest possible ROAS, but the variable you control most directly in that equation is your ad spend. Reducing your budget might improve your ROAS by eliminating less efficient transactions, but if a slightly lower ROAS leads to a significant increase in total revenue while the campaign remains profitable, those additional sales are still valuable.

Consider a full-funnel marketing approach. Upper-funnel activities, like brand awareness campaigns, work to generate demand, while lower-funnel efforts, such as retargeting ads, are designed to capture that demand. Imagine two apple pickers: Clyde climbs the tree to shake down apples, and Kelly collects them in a basket. If we only measure Kelly’s output, she appears highly efficient, while Clyde’s essential role goes unrecognized. However, without Clyde’s work, Kelly’s efficiency would plummet. In multi-channel campaigns, upper-funnel channels often show a high or unmeasurable cost per conversion, making them seem inefficient, while lower-funnel channels get all the credit. The crucial metric to manage, however, is the overall campaign cost per conversion or ROAS, not the performance of individual channels.

Ultimately, the focus should be on growth rather than pure efficiency. Using cost per conversion or ROAS as your main KPIs might feel secure, but it frequently leads to under-spending. These metrics can deceive you into abandoning profitable conversions under the pretense of efficiency. This isn’t to say that efficiency is unimportant. You should absolutely set a firm limit on what you can profitably spend. Once that boundary is established, direct your energy toward maximizing the number of conversions you can achieve within that financial framework. This is how you ensure you gather as much fruit as possible without letting it go to waste.

(Source: MarTech)