The metrics your agency won't tell you about

There are five numbers that decide whether a business grows: contribution margin, customer acquisition cost (CAC), lifetime value (LTV), payback period, and blended marketing efficiency (MER). Every one of them can be defended in a bank statement. None of them appear in a typical agency monthly report.

Contribution margin is the profit on a sale after all variable costs — cost of goods, payment gateway, shipping, returns, taxes. It's the number your finance team calculates and your marketing team refuses to look at because it makes their reported ROAS look silly.

CAC is the total cost of acquiring a new customer. Total. Not media spend divided by conversions. Agency fees, creative production, tools, salaries, freight — all in. Most Indian marketing teams under-report CAC by 40%.

LTV is the value a customer produces over their relationship with you. LTV is not a projection out to infinity — that's a spreadsheet fantasy. LTV should be measured on cohorts that have actually elapsed: 12-month LTV from a 12-month-old cohort.

Payback period is how many months it takes to recover CAC. Under 12 months is good. Under 6 is excellent. Over 18 means you're growing on cashflow, not on economics.

MER — blended marketing efficiency ratio — is total revenue divided by total marketing spend across all channels. It's the number that survives platform attribution decay. If your MER is under 2, you have a marketing problem. If it's over 5, you have an underinvestment problem.

These five numbers, defended monthly, tell you whether marketing is working. The other seventy metrics on your dashboard tell you whether marketing is busy.