Retail catalogs work depending on how you choose to add your data source, from which we can access your retail catalog.
If you’re providing the URL link for your hosted data source,
Pinterest will access your data source daily so they can dynamically create product Pins for each product in your retail catalog. Make sure your updated data source is available every day so your product details are up to date. You can even schedule your data ingestion in advance.
If you’re uploading your data source manually,
Pinterest will access your data source when it’s being uploaded, and every time you upload an updated one we can create product Pins, or update the metadata for existing Pins, for each product in your retail catalog.
Pinterest will alert you to any errors. It’s important to review and fix them as quickly as possible to make sure your product info is accurate and up to date. An error can mean your whole feed does not update, some items on your feed do not update, or you need to make some formatting changes.
We can process up to 20 million products per retail catalog.
For more information visit: https://help.pinterest.com/en/business/article/before-you-get-started-with-catalogs