These relationships can either bring great joy or can become the very cause of human frailty. In the play ‘Othello’ by William Shakespeare we witness the downfall of the main character Othello and the underlying factors which lead to his downfall.One of the main factors is the relationships he had with others.The relationship between Othello and Iago is built on friendship.he main weakness in Othello is his trustworthy nature from which derives other weaknesses, all of which ultimately leads to his downfall. Othello’s trustworthy nature is a weakness in his character; it is this characteristic which Iago preys on.