Why is there a coin shortage?

[LSLGuy]

Lots more discussion on almost the same topic here:

Is the coin shortage happening everywhere, or just in the United States?

(Inspired by @kayaker’s recent related thread) So, it now appears to be an established fact that there is a nationwide coin shortage. I’d been wondering why all of the self-serve checkout terminals, in all of the local markets that I frequent, have switched to card-only transactions–now I know.) It’s long been my assertion that of the four coins in common circulation – penny, nickel, dime, and quarter), not one has a sufficiently high denomination to be conveniently spendable. If you use …

Notice that this conversation started in late July and is still going on today. And references an earlier conversation from early July.