Rare; Expensive; Hard to Find; It’s a Venn Diagram, Not a Circle
I understand well the way market price moves to balance supply and demand (at least when talking about non-necessities in a free market, like collector coins).
I also understand that some coins are rare, but not particularly expensive (because not many want them), while other coins are not really rare at all, but very expensive (because so many people want them). Examples of the former include error coins (which can be quite remarkable, but the lack of a huge market keeps the price of most below the stratosphere); examples of the latter include the 1916-D Mercury dime, the 1916 standing Liberty quarter, and the 1893-S Morgan dollar (all of which are readily available—despite low mintages--in a wide range of grades, at any time, for one willing/able to pay the price).
And I’m aware of a lot of coins that seem difficult to find in certain grades, despite the fact that those coins are not particularly expensive.
I have also noticed that different coins have different “curves” in the graph of price vs. grade. Fairly common coins often are quite inexpensive in the middling grades, but can get suddenly expensive once in the higher AU grades and above (even before one gets to the top pop), while more scarce coins (e.g., the aforementioned three silver coins, as well as, say, the 1913-S Type 2 buffalo nickel, 1909-S VDB Lincoln cent and many others) are quite expensive even in the lowest circulated grades, but move up more gradually from there.
Understanding that the term “rare” is used loosely, often to describe coins that have a fairly low survival number, have a very high price tag, but are easy to find, I still am surprised when I can find very expensive (yes, many thousands of US dollars is “very expensive” to me) coins easily, while it often takes me months and months to track down far less expensive coins.
There’s not really a question here; rather, just expressing a bit of mystification.