Dark data is all the information companies collect but never use—often making...

https://www.bookmarking-keys.win/dark-data-refers-to-the-55-of-stored-information-that-businesses-collect-but

Dark data is all the information companies collect but never use—often making up 60-80% of stored data. It matters because holding onto this inactive data wastes money and space, sometimes costing businesses over $2.5 million a year