Crane repeatedly mentions fate in the story because the four men on the small boat are at the mercy of the sea. They try their best to get out of their predicament, but they barely manage to survive. They resent the fact that nature doesn’t give them any respite despite their current predicament and their tired bodies. The idea of humans being unable to control or alter their fate helps to accentuate the story’s theme of nature’s indifference toward man.
(plato)