It is often necessary to capture the history of changes made to a record for auditing purposes.
For example, a user may update a record with new values or delete an existing record. The updated or deleted record is saved along with the entire activity log such as old value, modified value, user who modified/deleted the record etc. This serves as documentary evidence for the sequence of activities taking place on application records.
Please note that the retained records are only for viewing/auditing purposes and cannot be restored.