The title is a quote from Kris Wilder.
Another thought from the week of insane business:
Fighting is complicated and hard and can take quite some time to learn.
Hurting, damaging, injuring, killing (whatever level of harm you wish to invoke) is relatively easy, and often the matter of a simple decision.
If you and I were standing in arms reach you could take me out. Orientation wouldn't matter-- standing side by side on the deck or walking past each other or sitting on the bus. If size and strength were too disparate, you simply employ a tool. All provided you could simply decide and act.
Most can't. Physically, most people have a host of precursor motions and telegraphs and intention signals. Mentally, it's not enough to simply have a good reason. Most people need a justification as well (killing someone to protect yourself or your children is a reason. "Because he was a bad guy" or "He was a piece of shit" are justifications.) Killing animals 'for food' is reason enough. We don't need to be angry, don't need to convince ourselves that the animal is bad. Socially, most people must go through steps as the conflict escalates, must seek hooks so that they can blame their own violence on the victim.
And so we have a tendency to kill animals, but to fight humans. And everything about fighting is inefficient. Bullshit dominance games played out physically.
And so, for self-defense, you don't 'fight off' an attacker. You hurt him. You make him pay. If necessary, you kill him. But you don't fight. He's a human too, and may have needed both a reason and a justification and all that jazz... which meant he wouldn't have picked you if he had any concerns about winning the fight. Work on conditioning and skill. They will never harm you. They will take you off the target list for many predators.
But if you, or your students, are on that list, the skills needed are qualitatively different than simply being a good fighter. You need to know how to break a human being (the easy part) and you need to be able to make the simple decision to do so. Not fantasize about the decision, not imagine your heroics. Simply decide and act.