Why are my autosave files not saving even though the setting is enabled??

Photoshop crashed due to ntdll.dll, costing me hours of work because the autosave feature is absolute dogwater. It never saves any progress - actually, it only ever 'saves' files that I had open but not edited at all, and NEVER the files that I was actually working on. Does it just not autosave edited .psd files? What's the point of that?

I have the autosave feature set to save recovery files every 5 minutes. How is it possible I can work for hours and not have a SINGLE recovery file after a crash. Every. Single. Time.

I shouldn't have to frantically save a several GB size file after every brush stroke because an inportant feature in a grossly overpriced product just DOESN'T WORK.