The Broad-Match Bleed on a Mature Catalog
A mid-size apparel seller spends $45,000/month on Sponsored Products across 40 ASINs. Over the last 60 days, ACoS has climbed from 22% to 34% while total sales are flat. The account has one large auto campaign and three manual campaigns. The auto campaign alone is 40% of spend with a 48% ACoS. Search term reports show the auto campaign is matching to broad, loosely related terms (e.g., 'women's hiking boots' when the catalog is summer dresses). The seller's target ACoS is 25% and gross margin supports it. The team is nervous about cutting spend because Q4 is approaching and they fear losing sales velocity.
1. Where is the ACoS problem most likely coming from, and what is the first structural change you would make?
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The auto campaign is the obvious culprit: 40% of spend at 48% ACoS is roughly $18,000/month at nearly double the 25% target. The search term evidence (hiking boots vs. summer dresses) shows the auto campaign is harvesting irrelevant traffic. The flat sales despite rising ACoS means the incremental spend is buying low-quality clicks, not incremental orders.
First structural change: harvest and prune the auto campaign.
- Pull the search term report, add irrelevant terms as negative exact/phrase.
- Move converting terms out of auto into dedicated manual exact/phrase campaigns with controlled bids.
- Tighten auto by using negative match types at the campaign level and consider narrowing to close-match or complements/substitutes rather than loose broad.
- Reallocate the freed budget toward the manual campaigns that are closer to target.
This is a surgical fix, not a blanket cut, so sales velocity is preserved on the terms that actually convert.
2. The team fears losing sales velocity before Q4. How do you frame the trade-off between cutting the 48% ACoS auto spend and protecting sales?
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Reframe the fear with numbers. At 48% ACoS the auto campaign is likely unprofitable or margin-dilutive; every dollar there returns less than the 25% target implies. Cutting irrelevant spend does not cut converting sales - it cuts waste. The risk of 'losing velocity' applies to converting terms, not to hiking-boot clicks on summer dresses.
Frame it as reallocation, not reduction:
- Move budget from the auto campaign's worst terms into manual campaigns on proven converters, so total converting volume is protected or grown.
- Set a phased plan: prune negatives week 1, shift harvested winners to manual week 2, then evaluate ACoS and sales weekly.
- Keep a modest discovery budget in auto so new converting terms can still be found - just not 40% of total spend at 48% ACoS.
- Use a guardrail: if sales drop more than X% after pruning, revisit; but expect ACoS to fall toward 25% while sales hold.