Dark data is the info companies collect but never use—like old files or logs....

https://www.bookmark-friend.win/dark-data-is-all-the-info-your-company-stores-but-rarely-uses-think-55-of-data

Dark data is the info companies collect but never use—like old files or logs. Up to 80% of stored data can be inactive, creating storage costs and security risks. It also clutters AI systems with useless noise, making insights harder to get