The OOTB rollout functionality does not provide any notification or messaging on failed or skipped item, all of them will say successful even though some were not processed. As a result, technical person need to triage the rollout line by line to identify the issue and error in order to fix.
The rollout functionality shows all items were process, even though some items were failed or skipped.
Proper messaging to notify content author which item has failed/skipped roll out and the reasoning.
Environment Details (AEM version/service pack, any other specifics if applicable):