We are almost at the limit of our 17 TB capacity in SharePoint and storage is getting very expensive. Clean up activities are now underway and we want to identify and stale sites that can be decommissioned completely. Our criteria is anything over 1 year must be marked for deletion. The problem is, in the SharePoint admin center, the last modified date only goes back to 11/4/20 on ALL OLD sites!
This is not accurate, I know most of these sites haven't been touched in over a year yet it tells me November they were all modified on the same date. Is there a background process running that is updating this 'Last Modified' time stamp? How do we properly identify stale sites if this date isn't accurate?