If you are an eCommerce company, Data Feed Watch (DFW) is the platform we use in order to optimize your product feed. It allows you to customize the product feed attributes before they are sent to Google Merchant Center (which is the tool that then uploads your product listings into Google Shopping, Google Product Ads, and Google Commerce Search). DFW is part of the reason why shopping ads are so successful.
Using DFW we have a live connection to the site. This means whenever there’s stock issues, page issues, 404 issues, DFW will see that and stop the ads. Where DFW also protects us, is if there is a product issue that GMC catches first, it gets "disapproved". If this continues to happen, it can ultimately lead to a GMC suspension which stops all ads. This is paid platform that we pay for because it helps us have a profitable shopping campaign for you.
On the other hand, if you were to send us a static spreadsheet version of your product feed, and a product encounters an issue, then Google Ads will still send traffic to those pages that you can’t commoditize. This means we will often be paying for clicks even though people can’t purchase the product. If we see the conversion value drop, we would have to stop the campaigns and investigate it manually in order to figure out what's causing the Smart Shopping campaign to spend without getting any conversion value.
It is important to have the most accurate and relevant data possible (product names, prices, images, descriptions, attributes, and much more); this way, Google can do the best job at targeting users based on that information.