Well here's a personal story about this... I recently moved my course syllabus to online only. It just exists as a page on my course website.

Then I ran into some problems because for certain administrative reasons, I needed PDF copies of my syllabus, including old syllabi from previous semesters which had already been overwritten on the website.

Good thing I keep version history on Github so I could revert to an older semester's version and print the site as PDF, but if I hadn't maintained versioning it would've been annoying.