&gt; wouldn&#x27;t the margin (revenue-costs &#x2F; revenue) already take into account the cost of acquiring customers?<p>Not necessarily. The word &quot;margin&quot; is very ambiguous because it could relate to many different types of margins.<p>In this case I think its safe to assume that &quot;margin&quot; meant the difference between the customer&#x27;s price and the direct cost of supplying that particular unit of product, ignoring overheads.