ROAS is the boardroom's favourite marketing number because it looks like accounting. Revenue divided by spend — clean, comparable, weekly. It is also structurally incapable of telling you whether marketing made money.
A 4x can lose money. A 2x can be a bargain.
ROAS sees revenue and media cost. It does not see product margin, shipping, payment fees, returns, discounts or whether the customer ever returns. A 4x ROAS on a 20%-margin product with heavy returns loses money on every order. A 2x on a 65%-margin product with strong repeat purchase is a bargain.
Same dashboard. Opposite truths.
“A 4x ROAS can lose money. A 2x ROAS can be a bargain.”
The attribution problem underneath
Platform ROAS also grades the platform's own homework. Last-click and view-through attribution routinely claim credit for customers who would have bought anyway — branded search is the classic case. The reported number is not just incomplete; it is optimistically biased by design.
Manage to contribution
The corrective stack: contribution per order after all variable costs; customer acquisition cost against that contribution; and lifetime value for customers who return. With those three, budget allocation becomes arithmetic instead of advocacy.
ROAS has its uses — as an early-warning signal inside a platform. As the number the business is managed to, it is a compass that only points at revenue. Profit needs better instruments.
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