A marketplace listing has two jobs. It has to be found in search, and it has to persuade the person who finds it to buy. Most listings that underperform are not failing because of the product. They are failing because of small, fixable problems that quietly push them down the results or put buyers off.
Here are twelve mistakes that come up again and again on Amazon and eBay, with the marketplace rules behind each one and what to do instead. The rules quoted are correct at the time of writing (October 2026), and both marketplaces update them regularly.
1. A main image that breaks the rules
Your main image is the one shown in search results, so it does most of the work. Amazon's requirements are strict. The main image must have a pure white background (RGB 255, 255, 255), the product should fill 85% of the frame, it should show one unit only, and it must not include text, logos, badges or props that are not included with the product. If no main image meets the requirements, Amazon may remove the listing from search until a compliant one is added.
eBay's picture guidance asks you not to add badges, logos, copyright notices or watermarks, because they can affect your listing's placement in search results.
Fix: photograph the product on white, crop tightly, and keep any graphics for the secondary images.
2. Too few images, or images too small to zoom
Buyers cannot pick your product up, so the photos have to answer their questions. Amazon recommends at least six additional images and one video, and says images of 1,000 pixels or more on the longest side enable the zoom function. eBay lets you add up to 24 pictures, with a minimum of 500 by 500 pixels and a recommended size of about 1,600 by 1,600.
Fix: plan a full set: every angle, the product in use, scale (next to something familiar), close-ups of materials and details, what is in the box, and a dimensions graphic.
3. Amazon titles written for the old rules
For years sellers crammed every keyword they could into Amazon titles. That approach now works against you. Amazon UK's current title requirements say titles must not exceed 75 characters including spaces, must not contain promotional phrases such as "free shipping", must not use characters such as !, $ and ?, and must not repeat the same word more than twice. Titles that break the rules may be automatically corrected or may not appear in search results.
Amazon has added an item highlights field that gives you a further 125 characters for details such as materials or uses, written as comma-separated phrases. It appears below the title in search results and on the product page.
Fix: lead with brand and what the product is, then the most important attribute. For example, "YourBrand Bedside Table with 2 Drawers, Solid Oak, Natural" says more than a string of keywords. Move the rest to item highlights.
4. eBay titles that do not match how buyers search
eBay's Best Match search, the default order of results, considers how closely a listing matches the buyer's search terms, alongside price, listing quality, completeness and your track record as a seller. eBay's advice is a clear, concise title with correct spelling and no more than 80 characters.
Common mistakes are vague titles ("Lovely wooden table"), filler words ("L@@K", "WOW"), and leaving out the brand, model, size or colour that buyers actually type.
Fix: write the title the way a buyer would search: brand, product type, model, key size or colour, and condition if relevant.
5. Empty item specifics and attributes
Item specifics are eBay's structured details: brand, size, colour, material and so on. eBay says completed item specifics are essential for being found on eBay and on external search engines, and that they power the filters buyers use to narrow results, especially on mobile. Some are required, and new or revised listings without them are blocked. Others are recommended, and skipping them simply makes you invisible when buyers filter.
Amazon works the same way through product attributes. A buyer who filters by size or colour will not see a listing that has left those fields blank.
Fix: fill in every required and recommended field that applies, and make sure the values are accurate. eBay's policy specifically prohibits putting information in the wrong field, such as a brand name in the size field.
6. Wrong, borrowed or missing product identifiers
Amazon checks EANs and UPCs against the GS1 database and treats numbers that do not match as invalid. Using purchased or incorrect codes can lead to listings being removed and selling privileges being restricted. On eBay, entering "Does not apply" or "N/A" for a required identifier when the manufacturer has provided one is against policy.
Fix: use the manufacturer's real barcode, or get your own from GS1 if you are the brand owner. Our guide to GTINs and barcodes covers this in detail, including Amazon's exemption for products without one.
7. Variations set up badly, or not at all
A variation groups closely related versions of a product, such as sizes or colours, onto one page. On Amazon this is a parent and child relationship. The parent is a virtual listing that only exists to connect the children; each child is a buyable product that differs by the variation theme, such as size or colour.
Two mistakes are common. The first is listing every size and colour separately, which splits your reviews and sales history and makes buyers hunt. The second is the opposite: grouping products that do not belong together. Amazon says products in a variation family must serve the same function and purpose and differ only in attributes such as size, colour or flavour. A laptop bag and a laptop rucksack should not share a page. Amazon also advises keeping size and colour out of the parent title and putting them in the child titles.
On eBay, one listing can hold up to 250 variations, across up to five details (such as size and colour) with up to 50 values each. eBay also recommends adding new stock to your existing listing rather than creating a new one.
8. Wasting Amazon's backend search terms
Amazon gives you a hidden field for search terms (sometimes called backend keywords). Buyers never see it, but Amazon uses it to match your product to searches. It is limited to less than 250 bytes, and Amazon may ignore the field if it contains prohibited terms such as brand names or ASINs.
Amazon's best practice is to use synonyms and spelling variations, avoid repeating words already in your title, use lowercase, separate words with spaces rather than punctuation, and leave out temporary or subjective words such as "new", "best" or "cheapest".
Bytes, not characters. Standard letters and numbers use one byte each, but accented letters and some symbols use more. If you use them, check you are still under the limit.
9. The wrong category
On Amazon, every product needs to sit in the right browse node, the specific "shelf" in Amazon's category tree. Amazon says ASINs without a browse node are not indexed and cannot be found in search, and that classifying too broadly ("shoes" rather than "women's road running shoes") limits discoverability. On eBay, the category decides which item specifics you are asked for and which filters your listing appears under.
Fix: choose the most specific category that accurately describes the product, and check it again whenever sales of a listing drop for no obvious reason.
10. Skipping A+ Content when you are eligible
A+ Content lets brand owners replace the plain product description on Amazon with images, comparison charts and structured text. Amazon says basic and Premium A+ are available at no additional cost. To use it, the products must be registered to your brand, which normally means enrolling in Brand Registry with a registered or pending trademark.
Many eligible businesses never set it up, or fill it with promotional claims that get rejected. Amazon's guidelines rule out pricing, promotional language, competitor comparisons, warranty information and shipping details, and reviews can take up to seven business days.
Fix: use A+ to answer the questions buyers ask most, show the product in use, and add a comparison chart across your own range. See our guide to Amazon Brand Registry if you are not enrolled yet.
11. Prices that look out of line
Price is not just about competitiveness. Amazon's fair pricing policy says it monitors prices, including delivery charges, and compares them with other prices available to customers. Setting a price significantly higher than recent prices offered on or off Amazon, charging more per unit for a multipack than for a single unit, or setting an excessive delivery fee can lead Amazon to remove the Buy Box or the offer itself.
In practice this catches businesses that raise prices on one channel to cover fees while selling cheaper elsewhere, or that forget to update multipack prices after changing a single-unit price.
Fix: review prices across all your channels together, not one at a time, and check multipack maths whenever you reprice. Our guide to winning the Amazon Buy Box explains how price interacts with delivery speed and seller performance.
12. Letting stock run out
A listing with no stock cannot sell, and on Amazon it cannot even be found: Amazon says an ASIN needs a buyable offer to be searchable. Worse is selling something you do not have. On Amazon, seller-cancelled orders count towards your cancellation rate, which should stay under 2.5% for orders you fulfil yourself. On eBay, cancelling an order because an item is out of stock counts as a transaction defect.
eBay offers an out-of-stock option for Good 'Til Cancelled listings: when quantity reaches zero, the listing stays active but hidden from search, and reappears when you add stock. eBay ends it if the quantity stays at zero for 180 consecutive days.
Fix: set reorder points for your best sellers, switch on eBay's out-of-stock option, and if you sell on more than one marketplace, sync your stock. Our guide to stopping overselling walks through how.
How to audit your listings in an afternoon
- Export your active listings and sort by sales. Start with the top 20, because that is where fixes pay back fastest.
- Check each main image against the rules above, on a phone as well as a desktop.
- Count title characters and check for repeated words.
- Open the attributes or item specifics and fill every blank that applies.
- On Amazon, check Manage All Inventory for search-suppressed or inactive listings, which is where title and image problems show up.
- Compare prices for the same product across every channel you sell on.
If you would rather someone else looked, book a free 20-minute demo and we will look at your products and the channels you sell on today.
Key takeaways
- Amazon main images need a pure white background, with the product filling 85% of the frame and no added text or badges.
- Amazon UK titles are now limited to 75 characters, with a separate 125-character item highlights field. eBay titles allow 80.
- Item specifics and attributes drive filters. Blank fields make you invisible to buyers who filter.
- Group genuine size and colour variations, but never combine different products on one page.
- Out-of-line prices, multipack pricing errors and stock-outs all cost you visibility as well as sales.