Meanings
third time is the charm; but more general; used as a lighthearted justification for doing something a third time, for including a third person, for taking a third drink, etc.
In meinem Leben hat mir das noch niemand gesagt. Noch eins, Herr Just; aller guten Dinge sind drei!No one has ever told me this in my life. One more thing, Mr. Just; all good things come in threes!