In an article which was mostly about another topic, I ran across this:
"...Ian Fleming, who used obscure and irrelevant detail to create a sense of reality in the midst of spy-story fantasy. In the James Bond novel “Thunderball” Fleming describes the villain’s super-fast yacht as having been built “by the only firm in the world to have successfully adapted the Shertel-Sachsenberg system to commercial use.” Novelist Kingsley Amis wrote that Fleming’s readers “couldn’t care less whether the Shertel-Sachsenberg system works the steering or the lavatory flush.”
Well, I was curious enough to google it. It's neither the steering nor the lavatory; it's the hydrofoil.
The point, according to Amis, is to take the “fantastic elements in the story” and use detail, however extraneous, to bolt “them down to some sort of reality.”
Actually hydrofoils are not at all extraneous to a high speed yacht; they're an essential enabler for its speed. Many boats can achieve high speed on flat water, but in choppy waves it helps immensely to be able to rise up above the chop rather than bash through it, and that's what hydrofoils let you do. Not every reader of that time would have known of Shertel and Sachsenberg's pioneering hydrofoil efforts, but boat fanciers would have, and that detail would ring true to them.
This is the thing that makes it hard to write a first-rate novel: you're writing for a lot of people, and many of them will have some particular domain of expertise which enables him to fact-check a tiny fraction of the details in the novel. To really ring true to all of them, you need to get those details right. Yet each of the readers knows different details. That means you need not just the level of expertise of each of them, but the level of expertise of all of them combined. Nobody can thoroughly accomplish that, but a few geniuses can do a tolerable enough job that readers will only very occasionally wince. (No, Mr. Bond, shooting a gun in an aircraft won't really cause it to violently depressurize.)
This is also why first-rate novels often take a while to really get appreciated. It takes years for readers with relevant experience to realize that not only they but experts in other domains approve of the book. It takes even longer for that realization to propagate to the chattering classes. Until then, the book is likely to be assigned by public opinion to the "trashy but popular" category.
If you want to write a boring novel like the only one of Amis's that I've read ("Lucky Jim"), your job is easier: rather than having a wide-ranging plot featuring matters of global importance and experiences which are so dangerous that most people shy away from them, you can stick to your own narrow, peaceful walks of life.
It's likewise easy to write the sort of truly trashy novel about which people say "lots of the details I know about are wrong, but the rest was entertaining". Most popular books really are trashy. But there are a few that will just keep on getting read and reread until the world realizes they have genuine merit.