Independent Study · Cross-sector · 2026

Why cost per lead is the wrong number to optimise

An independent analysis of what happens to pipeline quality when campaigns are optimised for volume.

This is independent study. It was self-initiated by Purple Ocean. No client commissioned it, no campaign was run, and there are therefore no performance figures to report. It is published so you can assess how we think about a problem before committing to work with us.

Context

Cost per lead is the most reported number in performance marketing and one of the least useful in isolation. It is easy to improve and easy to improve in ways that make the business worse.

The challenge

Set out a measurement framework that replaces cost per lead with cost per qualified opportunity, and define what has to be agreed with a client before a campaign goes live for that to be measurable at all.

The approach

  1. 01

    Define qualification jointly with sales before launch, not after

  2. 02

    Instrument the steps between form fill and conversation

  3. 03

    Compare campaigns on downstream conversion, not upstream cost

  4. 04

    Identify where honest attribution ends and estimation begins

Deliverables

What the engagement would produce.

  • Qualified-opportunity measurement framework
  • Pre-launch definitions checklist
  • Reporting template

Tell us what you are trying to grow.

A focused conversation, not a generic sales pitch. We will understand the business, identify the growth gaps and assess whether this is a strong fit.