Somewhere around IIRC Win8 Microsoft must have gotten
really lax about minimizing disk access. Windows started being slow as molasses on an HDD, even for stuff like opening the start menu.
This hurts performance a ton on SSDs, too, it's just less noticeable. Something that should happen so fast you can hardly measure how long it takes, takes... just long enough to notice, which may amount to 100x as long as it should take, but 100x a small number is still pretty small.