You need to elect a new Apostle to replace Judas.
You have two men. Joseph Barsabas surnamed "The Just", and Matthias.
Which one would most emotional humans pick? The one who's very name shows a reputation for being righteous, upright, and holy, right?
Nevertheless, SURPRISE! God chose Matthias.
Just goes to show you that man's judgments and God's judgments are two different things. He sees deeper. He often surprises our weak human prudence and wisdom.