I think that these Chinese companies just focus on mass production at a cheaper price. They don't really follow any strict quality guidelines. If they were to pay a little more attention to their products and spend a little more time in making them, their devices would be just as good as any other.
On the one hand, in this city there are containers where one can throw away useless cell phones and batteries, so not worry for me about it.
On the other one, whether Chinese or not, when a cell phone is damaged in anyway, it's cheaper and more reliable buy a new one that send it to the service to get it fixed so I don't care to keep spare parts for repairing.
I have a Chinese phone too that is now about one year old and it serves me good, but if it would fail, Chinese phones are so cheap that it will be easier buy a new one than repair it.
After all, if I save money to replace those with a renowned brand, why should I make an exception with these?