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

https://www.insert-bookmark.win/dark-data-is-all-the-unused-information-companies-collect-but-never-analyze-or

Dark data is the information companies collect but never use—up to 80% of data sits idle and hidden. This unused data can cost businesses millions each year, often around $2.5 million wasted on storage and management