Dark data is all the info your company collects but never uses—sometimes 60 to...

https://www.nav-bookmarks.win/dark-data-is-the-info-organizations-collect-but-never-use-study-says-60-80-of-1

Dark data is all the info your company collects but never uses—sometimes 60 to 80% of it sits inactive. It matters because storing and managing this unused data can cost millions each year, often $2.5 million or more