Earlier quoted context omitted.
They recalled a quarter million power banks because they were catching fire. Everybody uses the same factories and Amazon doesn't have better quality control than anyone else.
To be fair, Samsung had to scrap a whole phone model because of battery problems. The Boeing 787 suffered with problems of batteries catching fire (and according to some reports still does). It's a tricky problem to avoid.
With a power-supply it's not a hard problem to avoid. You have to hire independent engineers to evaluate the product design and establish testing procedures to verify that the product isn't unsafe. And you have to do QA and design verification during receiving on all batches of product to confirm that the manufacturer followed the design. I've never had a power supply catch fire and I've done some really dumb stuff in my lab. Frankly it's a matter of paying for UL/CE marks(including testing) and actually looking at the component layout, and Amazon doesn't strike me as the kind of company to respect that kind of QA/Verification work.
Batteries are a different story because they're basically tiny plastic bombs. Somehow Samsung managed to deliver almost 15 years of Android phones before having their batteries catch fire, and that was almost certainly a result of skipping essential QA/Verification processes because they've never had a problem before.