Looking for a commander-in-chief is normal. The embarrassment of not finding one is not. It shows that the Israelites (in this case, the Gileadites) are out of practice for warfare. Israel should have still been fighting against the inhabitants of the Promised Land, but they have been loath to do so for quite some time now (compare Judges 1:27–36). Consequently their military organization and power has weakened.
18 And the people, the leaders of Gilead, said one to another, “Who is the man who will begin to fight against the Ammonites? He shall be head over all the inhabitants of Gilead.”