What determines performance in shopping ads is often not the bid strategy but the quality of the product data. The most common feed errors and their effect on ads.
In shopping ads you don't choose keywords; Google and Meta decide which product to show for which search by looking at your product data. So in these campaigns most of the performance is determined not on the campaign screen but in the product feed.
1. Titles not written in the language of search
No one searches for the product you named "Classic Model 3-Pack" inside your store by that name. The title in the feed should follow the order people actually type: brand + product type + defining feature + size/color. The first words of the title carry the most weight, because the part trimmed in the list is the end.
2. Category assignment wrong or missing
The product category determines which competition pool the platform puts your product in. The wrong category means never reaching the right buyer. Choosing a general top category harms similarly: the more specific you are, the more accurate the match.
3. Images not following the rules
Images with "50% OFF" written on them, carrying a watermark or framed are rejected on most platforms. A rejected product never goes live, and this usually goes unnoticed — the campaign looks like it's working, but part of the catalog isn't live.
4. Stock and price data not reflecting reality
If the feed updates once a day, a product that sells out in the morning stays in the ad until evening. The clicking user meets an "out of stock" page. This is both a budget loss and, if repeated, lowers the account's credibility. Price mismatch is more serious; if the price on the site differs from the price in the feed, the product can be suspended.
5. Distinguishing fields left empty
Fields like GTIN, brand, condition, size, color, material are skipped as "not mandatory." Yet these fields directly increase the accuracy of the match. In particular, products without size and color information can't be shown to users searching for that feature.
6. Variants sent as a single product
When different colors and sizes of the same product are sent as a single record, the user can't find the variant they're looking for and lands on an irrelevant page. Variants should be sent as separate records, with a shared item group id.
The order in which to fix the feed
Instead of trying to fix everything at once, this order works:
- See the rejected products and close their reasons one by one — a product not live benefits from no optimization.
- Overhaul the title and image of the top 50 highest-revenue products.
- Increase the frequency of stock and price updates.
- Only then deal with the bid strategy.
Feed health must be monitored regularly
A product feed is not something set up once and forgotten. Small changes on the site side — a theme update, a change in category structure, a new variant field — can silently break the feed. The breakage usually shows itself not by the campaign stopping but by gradually decreasing impressions; that's why it's noticed late.
There are three numbers to check weekly: the number of products live, the number of products rejected and the number of products flagged with a warning. If there's a sudden change in one of these three, the cause should be investigated at once. Warnings are not rejections but are often the herald of rejection.
How do you open a Merchant Center account and connect a product feed?
For Google Shopping ads, you first open a Google Merchant Center account, verify and claim the store’s website, enter shipping and returns details, upload products through a feed and link the account to Google Ads. If any of these steps is missing, products either won’t be approved or won’t appear in ads.
- Open the account and enter your business details. Business name, address and contact details should match the information on your site.
- Verify your website. Verification can be done with the Google tag, an HTML file or a Search Console connection.
- Set up shipping and returns. Shipping information in the feed and on the site must match.
- Add your products. Method options: your e-commerce platform’s Google integration or plugin, Google Sheets, a file fetched from a URL at set intervals, or the API. The number of products and how often they change determine the method. Whichever method you choose, product IDs in the feed must not change over time; a product whose ID changes counts as a new product to the platform and loses its accumulated history.
- Link to Google Ads. Once linked, Shopping or Performance Max campaigns can use these products.
Once the link is in place, your products can also appear in Google’s free listings. This is a good opportunity to test feed quality without spending any ad budget.
The most common delay when opening an account is a site that doesn’t meet Google’s store requirements. Before applying, make sure the site has a contact page, terms of sale and returns, a secure checkout page and products that can genuinely be purchased. A site that is under construction or password-protected won’t pass review.
Checklist for finding product feed errors
Most feed errors are listed on the product issues screen in Merchant Center, but some drag performance down without any warning at all. The list below is designed to catch both:
- Warnings and disapprovals: Start with the issue affecting the most products. A single template error can affect hundreds of products at once.
- Structured data: If price and stock information on product pages is marked up as structured data, Merchant Center’s automatic item updates can reduce price and availability mismatches.
- Account-level requirements: Visible contact details on the site, a clear returns policy, a secure checkout page. Missing these can affect the whole account, not just individual products.
- Currency and tax: The price in the feed must be the same as the price the user will pay on the site.
- Links: The product URL in the feed should go to a page where the relevant variant is already selected.
- Custom labels: Writing information such as profit margin, season or best-seller status into custom label fields makes it easier to group products in campaigns.
- Main image: The product should be clearly visible on its own; lifestyle images showing it in use can go in the additional image fields.
Make these checks a weekly routine and note the number of problem products each time. A sudden jump in warnings on a given day is usually a sign of a change made on the site that day.
What’s different about the Meta catalogue?
On Meta, the product feed is uploaded to a catalogue in Commerce Manager and catalogue ads run on that data; the logic is similar to Google, but the most common error is different: the product ID sent by the Pixel doesn’t match the product ID in the catalogue.
When a product is viewed on the site, the Pixel sends a product ID. If that ID isn’t the same as the one in the catalogue, Meta can’t connect which product the person looked at to the catalogue. Dynamic remarketing doesn’t work, or shows the wrong product. The person sees an ad for an unrelated product instead of the one they viewed, and the ad reminds them of nothing. You can view the match rate between the Pixel and the catalogue in Commerce Manager; if it is low, this is the first place to look.
Matching problems mostly show up with variants. If every size and colour is listed under its own ID in the catalogue while the site sends the parent product’s ID, or the other way round, the link breaks. The fix is for the site and the feed to use the same ID structure; which structure you choose matters less than both sides being the same.
It is possible to use the same core data for both platforms, but because field names and required fields can differ, the output for each platform should be checked separately. You can find how the feed is managed on the advertising side on our e-commerce advertising page, and the steps needed to make sure sales are counted correctly in our conversion tracking checks article.
Frequently asked questions
Should I send the feed manually or automatically?
If the number of products is small and rarely changes, a manually uploaded file does the job. If stock and price change often, an automatic connection is mandatory; manual updates always stay behind reality.
Should I put all products into ads?
Usually no. Separating out products with low profit margin, uncertain stock or high return rate makes the budget more efficient.
The product description doesn't appear in the ad, is it still important?
Yes. Even if the user doesn't see it, the platform reads the description for matching. Descriptions you write yourself provide a better match than copy-paste manufacturer texts.
Why was my Merchant Center account suspended?
The most common reason is gaps that Google treats as misrepresentation: no contact details, returns policy or trustworthy payment information on the site, or inconsistent price or product information. After reading the reason in the notification and fixing the site, you can request a review.
What are free listings?
Products uploaded to Merchant Center can appear for free in some areas of Google, such as the Shopping tab, even without an ad budget. Visibility is not as high as with ads, but it is useful for confirming that the feed works correctly and seeing which products attract interest.
Can I use a single product feed for Google and Meta?
Most e-commerce platforms can generate output for both platforms from the same product data. Even so, because each platform’s required fields and category structure can differ, the two feeds should be checked separately and errors monitored in each platform’s own dashboard.
