Wait till you find out that that's how nearly all semiconductors are made: they're tested and graded. In some cases, like CPUs and memory, it includes testing each core and then disabling the bad ones. So a single-core CPU could be a dual-core CPU with one defective core, or a 4-core is a 6-core with one or two defective cores. In memory, it's bad banks or blocks which get disabled in testing and substituted by the spare blocks that are designed into the product for this purpose.
In many semiconductors (including the above), speed grading is also done: only some will manage the highest speeds.
So your 2GHz CPU might in "reality" be a "failed" 2.5GHz CPU.
It used to be a huge pain point / point of confusion / joke in the semi industry: "you can't test quality into a product!"
Well, when your statistical model shows that, sometimes the article works just absolutely perfectly, and sometimes it fails, and when it fails, it fails hard, in very specific, localized ways; well, yes, all you need to do is test to weed out the failed parts, and voila, quality.
Early fabs often suffered from truly embarrassing yield rates -- under 1% for example. I recall reading this about early Japanese transistor production I think it was; Intel and I assume others suffered from similar issues many times through history, as they brought up new fab lines. Everything from Intel's famously first DRAMs, to newer CPUs (I want to say the Pentium was one of them? or is that more just true of any chips ran through whatever the new fab process is?).
And the principle still applies to natural variation in process parameters, even as tightly controlled as they are. Doping levels usually being the biggest variance (isn't it?), affecting everything from voltage rating (hence the multiple grades of TIP31/A/B/C) to gain (hFE grades of 2SC1815O/Y/GR/BL, and everything (Vpo, gm, Rds(on)) of JFETs), to switching speed (hence clock ratings of CPUs). Why dispose of a part that runs a little slower but is otherwise perfectly serviceable?
Or I could equally well ask -- why not dispose of the parts that exceed the spec? Surely you feel just as strongly about being oversold, as undersold?

But overspec can be a problem too: typical example, fast modern epitaxial 2N3055s singing in old circuits that strung them up on wiring harnesses, or should I say resonant tank circuits -- yikes!
There's nothing wrong with this. Do you expect a butcher to discard the whole hog if one leg happens to be scrawny? Of course not. Do you expect a glass company to discard a whole lot of glass because of the parts with bubbles, even though it'll be cut into smaller sheets later, and they can cut around the imperfections? The world would be (even more insanely) wasteful than it is if we didn't do stuff like that.
Yup, exactly. Actually on the subject of meat, I wonder if standards could/should be updated to accommodate more kinds of defects. It's my understanding (at least over here; food laws do vary quite a bit around the world), finding a neoplasm or tumor is grounds to reject the carcass. Well, that might be warranted, but also what are the chances that the defect is benign? We remove benign tumors from humans all the time, and don't cull them.

The even less appetizing question also follows: even if it's cancerous to the animal, can it 1. cause illness in humans, under any conditions (i.e., if eaten raw, or worse), and 2. what about when safely cooked?
A valid counter-argument is, with how messy the meat industry is over here, it's probably not a good idea to give them this much leeway (i.e. to judge whether a defect is benign). A good counter-counter-argument being, well can't we just regulate them like normal countries? But, ah, the USA can't have nice things..

(and so I won't go any more political here).
Tim