I also will not henceforth drive out any from before them of the nations which Joshua left when he died:
The nations Joshua left at his death were not driven out afterward because Israel had broken covenant with God. The refusal to listen to His voice brought the withdrawal of His driving-out power from before them. Their enemies were therefore permitted to continue in the land as the direct result of persistent idolatry. What remained before them stood as punishment for ongoing disobedience rather than as an oversight in the conquest.
The nations Joshua left at his death were not driven out afterward because Israel had broken covenant with God. The refusal to listen to His voice brought the withdrawal of His driving-out power from before them. Their enemies were therefore permitted to continue in the land as the direct result of persistent idolatry. What remained before them stood as punishment for ongoing disobedience rather than as an oversight in the conquest.