Dark data is the inactive information organizations store but never use, making...

https://front-wiki.win/index.php/What_is_ROT_Data_and_How_Is_It_Related_to_Dark_Data%3F

Dark data is the inactive information organizations store but never use, making up 60-80% of all data. It hides valuable insights and costs companies millions—about $2.5 million a year on average