Dark data is the hidden information companies store but never use. It makes up...

https://mega-wiki.win/index.php/What_Is_Data_Curation_and_How_Is_It_Different_from_Data_Classification%3F

Dark data is the hidden information companies store but never use. It makes up 60-80% of all data, quietly eating up storage space and slowing systems. Ignoring it can cost businesses up to $2.5 million each year in wasted resources