The fear of he and his sons not being masculine enough is Okonkwo's biggest flaw. On page 33 Okonkwo says, "I will not have a son who cannot hold up his head in the gathering of the clan."
Okonkwo has excessive pride about his fighting and his success. On page 25 Unoka says, "You have a manly and proud heart. A proud heart can survive a general failure because such a failure does not prick its pride.
Okonkwo kills the messenger of the christian church in Africa on page 204, "Okonkwo's machete descended twice and the man's head lay beside his uniformed body". This is Okonkwo's reversal of fortune.
Okonkwo knows there will be consequences for his actions so that puts in a bad position. On page 205 he realizes what he has done, "He realized Umuofia would not go to war..He discerned fright with that tumult." Which this is the moment he made a critical discovery of realization.
The district commissioner and his people come to find Okonkwo, on page 206, "Which among you is called Okonkwo? He asked through his interpreter." This is the fate that cannot be avoided.
The feeling that made the audience have pity for the tragic hero was when the white men found Okonkwo hanging from the from the tree after he had killed himself, on page 207, "Then they came to the tree from which Okonkwo's body was dangling, and they stopped dead."