One thing that is easy to forget about, even with genuine components, is the QED process, "quod erat demonstrandum". It literally translates as "which was to be demonstrated". Batches are tested and the failure rate is noted (QED). Batches are often auctioned, and if not graded and priced as befits the QED rating, the less reliable are sold off much cheaper. One reason why cheaper computers etc. are less reliable.
In the past (80s and beyond) we were spoiled by Japanese production of tech toys, where reliability (and the integrity of managers) was a main driver for manufacturers. However, in China cost of production is a major driver, and line managers have been know to swap out supplied parts for cheaper components and pocket the difference themselves, and sod the company and its reputation.
The difference between 99.9% and 99.8% reliability does not sound like much, but the 99.8% will fail twice as often. Throw in a number of components in a system, and probability of failure increases exponentially. If an item is sold in lots of 10, I would not have too much cause for complaint if one of them fails, but if that caused costly damage to a model then I would naturally be upset.
Just my 2C