Clash of cultures
You buy batteries from China and announce that price maximum is something, usually very low for a quality product.
Chinese will say yes just to get the order and then make as good (or bad) batteries you can get with the given price and nice profit to the maker. So they fit the quality to (given) price and not the other way round. That's quite common internally in China so no problem with that in there: You get what you paid for.
Combine that to the 'cheapest wins' -culture in west (as if quality is given, while in reality it's not, seller cheats whenever he can) and you see that clash is inevitable.
From the chinese manufacturer's point of view the guilty part is the company who ordered the price very low and expected to get first-class products, not himself: He gave the best product you could get with that price.