Why is it that a number of the scores I have had for years have reached some sort of tipping point and are quite suddenly - all within the last year - starting to dissolve before my eyes?

That’s the Henle Well-Tempered Vol. I I bought as an undergrad. (Note the carefully applied contact paper to improve durability - Henle covers are not laminated. I don’t see folks using contact paper much anymore for books.) The bindings of some of my PWM Chopin and Kalmus Schumann volumes have completely split. I must say, the Dover editions are fine - the paragraph on the back cover of those editions talking about the binding and saying “this is a permanent book” seems to have been accurate. Of course, the notion of a “book” is itself not permanent - I see more and more iPads on music stands and piano racks.

Maybe my disintegrating scores are a sign of how much I practice? I should be embarrassed then at how long they have lasted.