A good defense starts with the line constantly crushing forward, closing the gaps and pushing the pocket. The secondary stays mobile and aware of where the receivers are and moves to them, instead of standing around in zone staring at the QB to make tackles AFTER giving up the play. And you HIT! I don’t care how many people get carried off the field or how many millions they’re getting paid. You make them fear for their lives to come into your territory. NFL defense is so damn soft anymore, I don’t even know how some of them have jobs.