If we examine how both of these central characters are introduced, we see that their failure is a result of the way in which they are singularly unsuited for the environment in which they find themselves. They are despised by Makola, the third man on the staff who is clearly below the other men because of the colour of his skin, and likewise the director clearly shows his contempt for Kayerts and Carlier when he says to his old servant:
"Look at those two imbeciles. They must be mad at home to send me such specimens... They won't know how to begin. I always thought the station on this river useless, and they just fit the station!"
Again and again in the text, emphasis is placed on how they are "insignificant and incapable" individuals set against the might of the solitude that they face. In particular, the reason for their failure is suggested by the author as being the way that society had made them:
Society, not from any tenderness, but because of its strange needs, had taken care of those two men, forbidding them all indepdendent thought, all initiative, all departure from routine; and forbidding it under pain of death. They could only live on condition of being machines.
Thus now, with the terrifying freedom that they are given by being left to run the station by themselves, do not know the first thing to do in terms of managing that freedom and making use of their faculties to accomplish the tasks they had been given. Thus it is that Kayerts and Carlier fail through their inability to act independently and think for themselves.