ROAS Is Dead. Here's the Metric Your Paid Team Should Own

Why ROAS misleads

Return on ad spend is the metric every paid team reports, and it's the one most likely to mislead you. ROAS tells you revenue generated per dollar of ad spend — but it says nothing about whether that revenue was profitable, whether it would have happened anyway, or whether the platform is taking credit for sales it didn't cause.

Worse, ROAS is trivially gameable. Cut your spend to only the cheapest, warmest audiences and your ROAS shoots up — while your growth collapses. Scale prospecting and ROAS falls — even if that prospecting is what makes the retargeting work.

The metrics that actually matter

There are two. Marketing Efficiency Ratio (MER) is total revenue divided by total marketing spend — it can't be gamed by shifting budget between platforms because it counts everything. CAC payback tells you how long it takes to earn back the cost of acquiring a customer; if that number is shrinking, your paid program is getting more profitable.

How to report on them

Build one dashboard that blends platform spend with your actual revenue source of truth, and report MER and CAC payback alongside (not instead of) platform-attributed ROAS. The platforms' numbers are still useful for optimisation within a channel — they're just not the number you should be managing the business to.

If your CFO can't tell whether paid is working from your report, the report is serving you, not the business.

When we moved Verde Skin to this model, the conversation with leadership changed overnight — from 'why is ROAS down?' to 'how fast is CAC payback shrinking?' That's the conversation worth having.