If you are launching a new product, there are a few ideas to get it out there.
Brand Recognition is a by-product of running advertising.
Start out with images you find around your site.
Sometimes when the budget is limited, having too many products in the shopping ads means the algorithm has trouble gathering conversion patterns in order to optimize because each conversion on each shopping ad/product is too spread out across the weeks/months, so the answer is to temporarily exclude products until the algorithm can get the hang of things. Then, with scale later on, those products' shopping ads can be re-included. Just because we exclude a product, doesn't mean it won't be purchased. It just means it might not work well as a shopping ad & the money could be better spent on other shopping ads to bring people to the site...but those people still might buy these products.