Most marketing is still sold and measured by one number: leads generated. It is the easiest thing to count, which is exactly why it is the wrong thing to optimize.
A campaign can drive more leads while quietly driving down the profit on each customer you acquire. Cheaper leads are often lower-intent leads. They cost your team time to qualify, they close at lower rates, and the ones who do buy tend to spend less. The lead counter goes up; the bank account does not.
The number that actually matters is profit per customer acquired — what it costs to win a customer against what that customer is worth over time. When you measure that instead, the whole picture changes. You stop chasing volume and start protecting margin.
This is why every Precision Profit Plan starts with your customer economics, not a list of tactics. Once you know what a customer is worth, you know what you can afford to spend to acquire one — and every channel gets judged against that, not against a vanity lead count.