In Judges, the people repeatedly rebelled, turn away from God, God is angered and allows the enemies to oppress them; the people cry out; God raises a judge to deliver them; there is peace and the pattern repeats itself. 

And it gets worse each time. It is a dark book about how the people of God repeatedly turn away from Him and sin. 

We also see repeatedly how this God is a holy God who loves His people. He graciously and repeatedly raises a judge each time to save His people. This is a tension that is repeated raised and not resolved in the judges, not when they get a king and is only resolved when Christ comes.