[the_Watchman]

I talked to a guy who supplied COSTCO in Arizona and the U.K. He said that they were hard-nosed about moving product. If your product wouldn’t move they wouldn’t waste shelf space on it.

[Tainan]

Good comment. "Big Boxes" like Costco do not "sell" your product. They merely give it shelf/floor space for the customer to buy it.
If it doesn't 'move' on its own rep or customer knowledge it will not occupy their space very long.

If you have a good selling product, one problem can be their demand for quantity. They want quantity for more and more stores and sometimes ramping up production to meet this demand can put financial strains on a supplier/manufacturer. If the market shifts and it doesn't sell, yo still have the financial obligations you entered into to get the quantity out.
just a consideration.