Start with break-even ACOS
If the product’s contribution margin before advertising is 30%, an ACOS above 30% generally loses money on the attributed order before wider effects are considered. That threshold is different for every SKU.
Use TACOS to connect ads and total sales
TACOS divides ad spend by total revenue. It can reveal whether advertising is supporting organic growth or whether the account is becoming more dependent on paid sales.
Every campaign needs a job
A brand-defence campaign, a new-product ranking campaign and a mature exact-match profit campaign should not share one target. Judge each campaign against its role.
Watch contribution, not revenue alone
Fees, discounts, cost of goods, returns and fulfilment can turn attractive ad-attributed revenue into weak cash contribution. Use SKU-level economics where possible.
Search terms are the operating detail
Target and search-term reports show where intent differs from assumptions. Consistent negative targeting and term harvesting are essential controls.
A more useful weekly review
Ask: Which campaigns changed and why? Where was spend wasted? Which search terms graduated? Which products lack budget? What happened to TACOS and contribution? What will be changed next?