Start with the product journey
The useful idea in the original catalogue-ad article was simple: show someone a product and give them a direct path to buying it. The customer should not have to search your store again to find the item from the ad.
Before spending, follow that journey yourself. Check that the advertised product opens the right page, the variant is clear and the product information agrees with the store. Check availability and the mobile buying experience too.
Keep product information dependable
A catalogue needs ongoing attention as products change. Establish how updates reach the advertising platform and who checks failures. An initial connection is not proof that every later change has reached an ad.
Choose the products and audience around the commercial purpose of the campaign. Reaching someone who has already considered a product is a different job from introducing your store to a new customer. Keep those objectives distinct when judging performance.
Check the result against the business
Do not treat a historical return-on-ad-spend example as a forecast. Compare advertising reports with store results using a consistent date range and an understood attribution method. Revenue alone does not establish profit.