Dark data is the stuff companies collect but never use—up to 80% of their...

https://www.ready-bookmarks.win/dark-data-is-the-inactive-info-your-company-stores-but-doesn-t-use-often-60-80

Dark data is the stuff companies collect but never use—up to 80% of their information just sits there. It matters because it takes up space, slows systems down, and can cost businesses millions every year in storage and missed insights