A lot of marketing conversations here center on cost per lead — which source is cheapest, which list is the best deal. It's the wrong number to optimize for on its own.

A $2 lead with a 1% conversion rate costs you $200 per actual deal. A $15 lead with a 10% conversion rate costs you $150 per deal — and is the "expensive" one. Cost per lead only tells you the entry price; cost per closed deal tells you whether you're actually making money.

I'd rather see someone pay more per lead from a source that converts than chase the cheapest number and drown in unqualified contacts.

Does anyone here actually track cost per deal by source, or does it usually stop at cost per lead?