In Shopping campaigns you do not write an advert. Google builds it from your Merchant Center feed, which means the product title, the main image, the price, the availability status and the attributes are your creative — and most stores are running whatever their platform exported by default. That is where the fastest gains usually sit. Titles that lead with the brand and the product type rather than an internal SKU description. Correct product identifiers, because missing GTINs limit where an item can serve. Colour, size, material, age group and gender populated, because those attributes decide which queries you can match. Images that meet the requirements without watermarks or promotional overlays. Prices and stock that match the landing page, because mismatches cause disapprovals that silently remove products from the auction. A store can spend months tuning bids on a feed where a third of the catalogue is ineligible and never see the cause in the campaign reports.
The technical SEO problem is different from every other sector because it compounds. A brochure site has thirty pages; a catalogue has thousands, and every structural mistake is multiplied by the product count. Faceted navigation is the usual culprit. Filters for size, colour, price band and brand combine into an effectively unlimited set of URLs, each one crawlable, most of them near-duplicates of a page that already exists. Crawlers spend their time on parameter combinations nobody searches for, real product pages get crawled less often, and the index fills with thin variations that dilute the pages you actually want ranking. The fix is a decision, not a plugin: work out which facet combinations have genuine search demand and deserve a real indexable page, then make sure the rest are consistently handled — canonicalised or blocked, but not both at once, since a URL blocked in robots.txt can never be read to discover the canonical you set on it. Add discontinued products, variant duplication, paginated series and manufacturer descriptions copied across the industry, and you have the four issues that account for most lost ecommerce organic traffic.
The economics are where good campaigns still lose money. A revenue-based ROAS target ignores the two numbers that decide whether a sale was worth making: gross margin and returns. At a 20% gross margin you need a 5x return on ad spend simply to stand still, and that is before you have paid for picking, packing, delivery or the proportion that comes back — and in clothing and footwear the return rate is high enough to change the answer entirely. Different products in the same account therefore need different targets, which is what custom labels in the feed are for: margin bands, seasonality, stock depth, clearance. The same discipline applies to channel roles. Shopping captures people who already know the product, Search covers category and problem-led intent plus defending your own brand name against resellers, email and retention carry the repeat purchase, and Performance Max blends all of it while giving you far less visibility into what it bought. Retail seasonality then concentrates the risk: a large share of the year's trading arrives between Black Friday and Christmas, so a feed or tracking problem discovered in November is not a technical issue, it is a lost quarter.