Kurtz’s fiancée “the Intended” is perhaps the person most devoted to him and convinced that he is out in the
'When I had a chance I begged him to try and leave while there was time; I offered to go back with him. And he would say yes, and then he would remain; go off on another ivory hunt; disappear for weeks; forget himself amongst these people -- forget himself -- you know' (pg. 95).
Kurtz apparently wants to go home, but some evil force, some part of him does not want to let go of the ivory hunts and other “thrills” of the jungle. He tends to “forget himself,” his identity as an educated humanitarian with a devoted fiancée, and only remembers his near-supreme power. When he finally is forced to go home, it is too late for him to make it there alive. Kurtz has failed the Intended in a most chilling way.
As he looks back on all of his failures, Kurtz realizes that he has failed himself as well. Marlow’s careful observation of Kurtz confirms Kurtz’s self-realization:
I saw on that ivory face the expression of sombre pride, of ruthless power, of craven terror -- of an intense and hopeless despair. Did he live his life again in every detail of desire, temptation, and surrender during that supreme moment of complete knowledge? He cried in a whisper at some image, at some vision -- he cried out twice, a cry that was no more than a breath:
'The horror! The horror!' (pg. 118)
As his life flashes before his eyes, Kurtz clearly sees his enormous failures weighed against his superficial successes. His cry of “The horror! The horror!” is somewhat of a mystery, but it can be reasonably interpreted that Kurtz is referring to the atrocities committed by his own hands. All of this failure and horror point to the idea that Kurtz has failed himself. For all his education and European upbringing, he has succumbed to committing horrible acts and failing everyone around him. Other characters had commented that Kurtz could have been a great man, but he chose to become a terrible tyrant. Kurtz is a complete failure to himself for not reaching his full potential as a human being.
Throughout the novella, Kurtz’s upside-down life is vividly depicted by sharp contrast of his past image and his horrible deeds. It is an appalling phenomenon how a person with well intention completely lost and turned into a demon in the darkness. His failure is not alone and not his own; he failed the whole world. However, on closing the book, I can’t help but keep thinking – what about the Europeans? Do they fail him, too? Is it a good idea that “we” developed human beings to save primitive people “in the nature of supernatural beings” at first place? Will Marlow or anyone else turned into a same demon put in the same situation?