You can do everything right, and still die. You can be better than your attacker on any other day, but not today. You have all the tools you need, but you had not time to bring them to bear.
We all need to come to terms with the fact that our skill set, our mindset and our tools can be rendered useless if the day ever comes. We need to understand that everything can be in our favor and we can still come in second place. Life is unpredictable and we need to accept the fact that there may come a time in which we do not have an answer for the problem.
But this should never be the default. We should always train to the best of our abilities. We should always be looking for an edge. We should expand our skill set to allow us to solve more problems. We should enhance our awareness to increase our safety. Even though there may come a day where you lack an answer, the more you work, the less likely that day will come.