The Health tab of Settings → Media.
Shows how many files are where, and what, their library's storage
profile and rendition profile want (V205), and lists the ones the reconciler
(Storage.Workers.ReconcileJob) has not brought up to date yet: copies
missing or on buckets the profile no longer uses, renditions missing or made
from an older spec. The reconciler runs by itself, a run per library
(Storage.Jobs.Reconcile, watched on Admin → Jobs and on the Libraries tab);
"Reconcile now" only starts those runs sooner.
The report counts every file, so it is read when the tab is opened (and on Refresh), not when the settings page loads.