Amazon has been rather liberal in their acceptance of returns and offer of refunds in my experience, and I used to make good use of the “Amazon warehouse deals” of returned-goods to save a few bob on something that maybe didn’t work out for a previous purchaser.
But within perhaps the last two years, I’ve discovered that if I want to have a reasonable certainty that it will work out of the box, I need to purchase “new” rather than returned from Amazon. I’ve had the same experience over a longer time period with certain branches of Brick & Mortar home-improvement stores, where I’ve learned to open the package before purchase to make sure that it is not someone’s “return” of a broken or non-working item.
I appreciate “no questions asked” return policies when something turns out to be not what I wanted or needed, and will clearly tell them on my returns when something is defective. But there have been occasions where I suspect someone has been attempting to scam the “big corporation” by returning the broken item they replaced in the packaging of its replacement; and I’ve been the one burned.