Lightroom Classic CC not showing all images on a card during import

I have a less sinister, but also annoying, symptom of the same kind: with a card or camera connected, LR will recognize the card or camera, but will say "no images to display." I then disconnect, restart LR, plug the thing back in, go to the import dialog, and usually find the images. Some times it takes more than one iteration. I too hope that I have not lost any images -- there have been occasions where the first image of an import set is not imported, and in that case I copy the source from the card or camera to a folder on my computer, then import to LR from there. The mysteries of the import dialog multiply, and are unpleasing.

Note that this happens both with a Win10PC (my work computer) and a MacBook Pro with the latest MacOS (at home). It happened when I was using a card reader with a CF card from my Canon EOS 1Dx, and still happens now I'm using a direct USB 3.0 connection to my Leica SL. So the glitch appears agnostic both as to the type of file involved and the type of connection used.

I note that others have pointed out that using LR's import dialog is forcing LR to "do things it is not good at." Not much of a feature then. The recommended (and tedious) work-flow is to copy direct from camera or card to a folder on computer, then import to LR from there. It is true that this results in a faster import sequence once the import dialog is invoked, but it strikes me as a rotten failing of LR to have since its primary raison d'être is to help organize photographs. Sigh.