Many years ago, I worked as a consumer electronics tech and it was understood that a certain percentage of parts would be faulty and break down quickly, or never work at all. Probably everyone has seen a TV fail to turn on when the switch was turned. Or an air conditioner fail to start up, when turned on. And, every tech seems to have had the experience of installing a brand new part, and still having the original problem when the device was turned on. Then, after some frustrating trouble-shooting it would turn out that the “new” part was defective. It could be maddening.
Also, some parts are under high stress at certain times and some parts will fail at those times. To build a device with truly high quality parts would probably result in a price most consumers would never be willing to pay. Maybe it’s just a matter of trade-offs. Somewhat lower quality parts, for a lower end price.