What does this verse tell us about sin?

Judges 4:1 (ESV)

1 And the people of Israel again did what was evil in the sight of the LORD after Ehud died.

Take away whatever influence Ehud may have exerted, and Israel immediately goes astray. That is what sheep do in the absence of a shepherd. It is the same monotonous routine. For it is difficult to be creative in sin. We tend to do the same thing over and over again.