Earlier quoted context omitted.
Many years ago a friend of mine proposed a theory of his (I use the word "theory" in the loosest possible sense here, more student dorm than lab) that sounded a lot like this. In his version, most of everything is shit. Most music is shit, most movies are shit, most pizzas are shit. Only a minority of any given thing is actually of high quality. I haven't seen much over the years to convince me that he or you are wro…
90% of everything is crap. -- Sturgeon's Law
But a few years ago, I found out that his short stories had been collected in a multi-volume series, and I started reading them.
I was pretty crestfallen; I don't use the term "cringey" much, but that's how I would describe a lot of them. I intended to read the whole series, but haven't and probably won't.
Not all of them were terrible, but the famous short stories he wrote were presumably famous because they stood apart.
Also he seems to have flirted with Dianetics in its early days, even basing some of his fiction on it.
So, I guess when you look deeper, he himself proved the law. On an individual basis, you have to produce a lot of crap to generate a masterwork.