If Joshua demonstrated the correct response to learning the lessons of the Exodus and the Torah given by God, then the period of the judges is just the opposite.  These people were ignorant of what God had done (like us), ignorant of His law (like us), and fell into a mood of complacency that became their downfall (like us).  The period of the Judges is a time from which we must learn, or prepare to face the same kind of temptations and alienation from God they did.