I used to think that made sense (as sibling mentions, Spolsky's "fire and motion" thesis)... until I worked at large-ish tech company whose internal platforms also kept doing this. Heck, the platform I owned also underwent a couple cycles of this. And so a large part of our work was just doing the Red Queen's race of deprecations and migrations.

So it was definitely not "fire and motion," as there was no competition. I think platforms genuinely need to evolve as new use-cases onboard and technology progresses, and so the assumptions underpinning the platform's design and architecture no longer hold.

However, I do think a small part of the problem was also PDD: "Promotion Driven Development."