I don't know whether there is a specific japanese cultural explanation, but in general it often was. In winter when it was cold, those who lacked the strength to go on, layed down in the snow to rest forever.
I don't remember who said it, but a statement that has stuck with me is:
The moment when the most you can do is less than the least you need to do, you die.
I don't remember who said it, but a statement that has stuck with me is:
The moment when the most you can do is less than the least you need to do, you die.