When the group project tanks, the leader says “we” first and “I” right after.

Taking the group’s hit in public and your own part in private is what makes people willing to be led by you again. Pointing at the member who did not do their bit might be accurate, but it tells everybody what you would do to them next time. Shared failure stays shared, and your specific share is still yours to name.

If something you were running went badly, write two sentences before the meeting: what the group missed, then what you personally would do differently. Say them in that order. Handle the individual conversation quietly, afterwards.