What does Judges 11:32 mean?

Then Yahweh’s Spirit came on Jephthah, and he passed over Gilead and Manasseh, and passed over Mizpah of Gilead, and from Mizpah of Gilead he passed over to the children of Ammon.

Jephthah vowed a vow to Yahweh, and said, “If you will indeed deliver the children of Ammon into my hand,

then it shall be, that whatever comes out of the doors of my house to meet me, when I return in peace from the children of Ammon, it shall be Yahweh’s, and I will offer it up for a burnt offering.”

He struck them from Aroer until you come to Minnith, even twenty cities, and to Abelcheramim, with a very great slaughter. So the children of Ammon were subdued before the children of Israel.

Jephthah came to Mizpah to his house; and behold, his daughter came out to meet him with tambourines and with dances. She was his only child. Besides her he had neither son nor daughter.

When he saw her, he tore his clothes, and said, “Alas, my daughter! You have brought me very low, and you are one of those who trouble me; for I have opened my mouth to Yahweh, and I can’t go back.”