Dark data is the information companies collect but never use. It’s usually...

https://wiki-aero.win/index.php/How_Does_Apache_Iceberg_Fit_into_File_and_Object_Metadata_Tables%3F

Dark data is the information companies collect but never use. It’s usually older files or unused backups, often making up 60-80% of all stored data. This hidden bulk slows systems, drives up storage costs, and wastes about $2.5 million annually on average