Online shopping has two dominant phases: the browse and selection phases. During the browse phase, a user looks at all the products on offer and makes a choice, usually by parking the products he’s interested in in a separate tab or adding them to a wish list.
The selection phase involves the user going through the candidate products he has saved and then adding the ones he wants to buy to his cart. It’s only after the selection phase is complete that the user then goes through checkout.
Imagine the user, say, Jonah is shopping for t-shirts. T-shirts have separate attributes. There are differences in design, colors, and patterns. It might be tempting to put red and blue t-shirts in a separate listing but that is actually a bad idea. It makes the browsing so much more convoluted. Jonah will spend a lot of time going back and forth between t-shirts that are exactly identical except for the color and that’s just not a good use of his time.
Show all variants under a single listing
All product variants should be shown under a single product listing so that a customer browsing knows exactly how many variants there are. Failing to do this might result in Jonah clicking off because he wants a blue t-shirt and the listing only has a red one.
Use thumbnails to indicate additional variants
Small thumbnails under the product image are the best way to show additional product variants. They outperform both swatches and plain text.
When can you break the separate listing rule?
You can list different variants of a product as separate items if and only if your store has limited inventory (ten unique items or less). If you only sell one type of round neck t-shirt for example, then you can have separate listings for your red green, and blue t-shirts.
When the inventory is small and there isn’t much to browse, then there is little chance of a customer being confused by separate but similar products with only slight variations in attributes. Even then, you have to make sure that other variants are easily discoverable by including their thumbnails on a featured product’s page.