וְנָתַ֤ן מַלְכֵיהֶם֙ בְּיָדֶ֔ךָ וְהַאֲבַדְתָּ֣ אֶת־שְׁמָ֔ם מִתַּ֖חַת הַשָּׁמָ֑יִם לֹֽא־יִתְיַצֵּ֥ב אִישׁ֙ בְּפָנֶ֔יךָ עַ֥ד הִשְׁמִֽדְךָ֖ אֹתָֽם׃
그들의 왕들을 네 손에 붙이시리니 너는 그 이름을 천하에서 제하여 버리라 너를 당할 자가 없이 네가 필경은 그들을 진멸하리라
Or HaChaim on Deuteronomy
ונתן מלכיהם בידך, "He will deliver their kings into your hand, etc." You will capture them alive. We have proof of this in Joshua 10,26.
Sforno on Deuteronomy
ונתן מלכיהם בידך והאבדת את שמם, for allowing any of these Canaanites to survive would become an ongoing source of irritation for you, as demonstrated by the young Haddad, sole survivor of the people of Edom, who became a lifelong source of irritation (militarily) for such a powerful king as Solomon. (Kings I 11,14 and onwards)
Tur HaArokh
ונתן מלכיהם בידך והאבדת את שמם, “He will deliver their kings into your hand and you will cause their reputation to perish.” The few Canaanites remaining in the land during that time will not amount to anything, politically or militarily. Anyone who tries to make a stand against you will fail.