Dark data is all the information companies store but never use—sometimes 60-80%...

https://www.red-bookmarks.win/dark-data-is-the-information-your-business-collects-but-never-uses-often-55-of

Dark data is all the information companies store but never use—sometimes 60-80% of it. This hidden data adds up, wasting around $2.5 million a year on storage and management