Cheap clicks feel like progress. So do cheap leads. But the number that pays the bills is what it costs to win a client — and what that client is worth.
Measure the whole journey: from the ad or the post, to the enquiry, to the call, to the sale. When you can see it end to end, you stop rewarding the campaigns that only look good on a dashboard.
Judge every decision by cost per client. Everything else is a guess.