Having had recent, in-depth personal experience with these things, PART of the answer is that they're crap. They almost don't exist, in that a working one is ra

Having had recent, in-depth personal experience with these things, PART of the answer is that they're crap. They almost don't exist, in that a working one is rare. Each one is really just a probability of functionality; a non-functional replica of some ideal product. They will almost certainly break with relatively low amount of standard usage (or the usage they support is ridiculously unrealistic, like not using them in temperatures over 86 F). And this is because their pipelines are optimized to produce the parts as cheaply as possible; just enough to physically exist and work, perhaps, a few times. They will be sold under different names over time so people won't be able to share their experiences. And of course, they are made in places where human suffering and pollution are not penalized.