I used lots of 1.44MB floppies in the early 90s and generally had few, if any problems, as I recall. But later in the decade, I had more and more trouble, and

I used lots of 1.44MB floppies in the early 90s and generally had few, if any problems, as I recall. But later in the decade, I had more and more trouble, and by the late 90s or early 2000s they could absolutely not be relied upon at all. I wonder if you went through all your HD 3.5" floppies, and sorted them by manufacturing date, if you'd find a trend showing the early ones being more reliable than the later ones.