[Inkscape-user] next/previous zoom survives closing/reopening file

Hi Friends, Yes, another weird question :-p. I've noticed that next/previous zoom survives after closing and reopening a file. To my simple way of thinking, next/previous zoom is similar to Undo/Redo. In both cases, Inkscape "remembers" what came before and what happened next. Why can't Undo/Redo survive closing and reopening the file? Wouldn't that be awesome?! Could someone give a simple, or very generalized explanation why Undo/Redo can't survive closing the file, but Next/Previous Zoom does?

Thank you very much :-) brynn