Dark data is the inactive or unused information organizations accumulate, often...

https://www.slideserve.com/aaron_ward92/why-does-dark-data-create-operational-drag-for-it-teams

Dark data is the inactive or unused information organizations accumulate, often making up 55% of stored data. It raises breach and ransomware risks since unmonitored files may hold vulnerabilities. Storing this data also wastes money—sometimes $2