Why Blended ROAS Is Lying to You

Standard ROAS math is simple to the point of being reckless. Divide revenue by ad spend, get a number, call it a day. It ignores COGS. It ignores payment processing fees. It ignores returns, chargebacks, and fulfillment costs entirely.

Here's what that looks like in practice. Say you sell a $50 product with a 4x ROAS. On paper, that's a great campaign. Now factor in a 55% cost of goods and a $6 Amazon referral fee. Suddenly that "profitable" order is losing money, and the dashboard never told you.