Compare that to Amazon, which I have zero trust in. I absolutely can't trust the reviews, and I can't trust any products are genuine (even for minor things: my last purchase several months ago were steel wool dish scrubs - name branded, but I'm certain they were fake). I also don't trust them to do anything about it, because I've reported fake reviews, and fake products several times, and all of those sellers are still selling with thousands of 5 star reviews. The only thing it has going for it is price and convenience.
In this case, it began deteriorating with steel 'hairs' coming undone immediately after first use. Should I be concerned about that? Is it even steel wool or another material? If the latter, is it safe and tested against items that humans will be consuming food from? Is it sterile? Were some other chemicals used to treat it for something as trivial as attempting to match the colour of the brand?
There is no chance that Costco doesn't use analytics. They might not A/B test their online button colors for highest conversion rate, but I'd bet they have their own set of analytics to determine product quality, sales, returns, viability, etc.
https://phf.tbe.taleo.net/phf02/ats/careers/v2/viewRequisiti...
If someone says "I hate traffic," you probably wouldn't assume they're talking about the entire spectrum of traffic.
This is part of why costco is so successful. When I buy a kirkland brand item, I know with like 95% confidence that I'm getting a quality product. Not only that, but they go through heroic lengths to vet the other products that they put out. If you buy extra virgin olive oil at costco, it's very likely that it's pure extra virgin olive oil.
They turned retail on its head after 30 years of abuses by people focused on quarterly earnings and selling their brand into the ground. Instead of making the product as shitty as possible and charging as much as possible, costco hard caps their margins and will then invest money to optimize their suppliers manufacturing process to pass the savings along to their customers.
The big thing with costco is trust. I trust them and their products because they've earned it. In the rare event something is wrong with their product, they'll make it right with basically no questions asked. They used to do this to an absurd degree until people started abusing it.
Compare that to the amount of vetting I have to do for almost every amazon purchase now. It's a huge headache, and there's a lot of stuff I just won't buy off of amazon anymore.