As risking ones life is part and parcel of being a warrior, a person on that path has to reconcile themselves with the possibility (and natural inevitability) of their death. The Samurai wrote about it fairly constantly. If death on the battlefield didn’t claim them, the possibility of being ordered to commit seppuku was always around the corner.
One of those writings, the Budoshoshinshu, has the following to say about it:
“One who is supposed to be a warrior considers it his foremost concern to keep death in mind at all times, every day and every night, from the morning of New Year’s Day through to the night of New Year’s Eve.”
“As long as you keep death in mind at all times, you will also fulfill the ways of loyalty and familial duty. You will also avoid myriad evils and calamities, you will be physically sound and healthy, and you will live a long life. What is more, your character will improve and your virtue will grow.”
Another passage says:
And all this misfortune springs from his not remembering to keep death always in his thoughts. But one who does this whether he is speaking himself or answering others will carefully consider, as befits a samurai, every word he says and never launch out into useless argument. Neither will he allow anyone to entice him into unsuitable places where he may suddenly confronted with an awkward situation, and thus he avoids evils and calamities. And both high and low, if they forget about death, are very apt to take to unhealthy excess in food and wine and women so that they die unexpectedly early from diseases of the kidneys and spleen, and even while they live their illness makes them of no use to anyone. But those who keep death always before their eyes are strong and healthy while young, and as they take care of their health and are moderate in eating and drinking and avoid the paths of women, being abstemious and moderate in all things, they remain free from disease and live a long and healthy life.
Basically. If you are putting your life on the line, make it worth it. If you keep in mind the fact that if you fight you may be killed, you will choose the proper time and place to risk your life. The knuckleheads killed in barrooms over “respect”, compared to a person who dies rescuing another is a good example of this concept.
The first time I seriously thought that I was going to die was in an auto accident when I was 18, but that happened so fast that it didn’t dawn on me until after the car stopped spinning. The first time I remember thinking “this could be the end of me” was when I was rappelling. I was 19-20 years old at the time. With little training and my gear consisting of nothing but an anchor rope, a carabiner, and a rope harness…dumbass that I was…I went off to a local cliff. I came off the rope, fell down the cliff (50-75 ft/slightly sloped) , bounced twice, and landed hard. Fortunately the rope wound around my arm, burning me pretty badly but slowed me down enough to just knock the wind out of me……then there was the time I tried a slack jump off of a railroad trestle….
Currently my career track has been diverting me farther and farther from “the road” so the odds of meeting my maker on that venue have been somewhat reduced. However I do still manage to get out on the street and lock a person up on the odd occasion so I do think about the possibility every now and then. My hope is that if it ever does happen, that I will “take it like a man”. I have no plan of going out begging for my life or crying and screaming as I have seen in some chilling training videos. I plan to go out angry, swearing and shooting, or at least trying to.
When it comes time for the “we all have to go sometime” moment, the only thing I hope is that it sneaks up on me and is quick. Preferably in my sleep. Otherwise suddenly will suffice.
the things worth believing in 
Reminds me of a Sufi story: people on a boat in a storm throwing things overboard to keep from sinking and the old Sufi Sheik just sitting there.
“Don’t you realize there’s only half an inch of wood between you and death!” one of them yelled at him.
“That’s a lot more than there is on land,” he replied.
We say that the hour of death cannot be forecast, but when we say this we imagine that hour as placed in an obscure and distant future. It never occurs to us that it has any connection with the day already begun or that death could arrive this same afternoon, this afternoon which is so certain and which has every hour filled in advance. ~Marcel Proust
Given the habit of the the Japanese (especially those in the martial sub-culture) to codify their writings, it might be of value to view the ‘death’ that they write about as only a surface-level topic. Their word for death (shi or shin) can be written to mean spirit, mind, or just the number four.
Combine that with the Shinto customs of worshiping dead ancestors to access the spirit-world, and maybe the authors are referring to always be mindful of your spirit so that you remain centered and unable to be gripped by fear, avarice, etc.
Furthermore, if you combine the definition of shi-as-the-number-4 with the void of death (ku), you get the five elements (chi-sui-ka-fu-ku), or five rings, that are rampant throughout Japanese martial philosophy.
It’s always fun to play with the Japanese language. =P