The cost of acquiring a customer relates the resources employed in the search for new buyers with the customers obtained. In order to use it, it is necessary to define the period, the expenses included and the criterion by which a customer is considered new.
In a hypothetical example, a €1,000 campaign produces twenty first purchases attributable to the campaign: the average advertising cost is €50 per customer. This figure does not necessarily include commercial work, software, and material preparation. Defining the scope prevents it from being mistaken for the total cost.
Comparison with the first-order value alone may be insufficient. Margins, returns, and subsequent purchases must be observed. Repurchase expectations are assumptions to be verified, especially when customer behavior changes or the observed base is reduced.
Attribution also requires caution: those who buy may have encountered multiple channels before the campaign. I propose to keep consistent criteria and separate measured results from estimates. The number serves to compare initiatives and correct spending, without turning an average into a promise on the value of each individual customer acquired.