What does Judges 5:17 mean?

'Gilead stayed across the Jordan. Dan hung back with his ships. Asher sat by the coast, staying by his harbors. But Zebulun risked their lives, and Naphtali did too, out on the battlefield.' Judges 5:17 - Modern Text Bible

(Some tribes didn't show up, choosing safety or business over the fight. But Zebulun and Naphtali are praised for risking everything.)