how is the sequence in the boston hotel the climax of the play ? exlplain what happens and how that relates to everything going on in the play between willy and biff

In Act II, Scene VI,  Miller finally gives a full explanation for Biff's refusal to take a summer school course, the critical event that determined his chain of failures. It is Willy's infidelity that prompted the change in Biff, as he learned that his father was having an affair with the woman in Boston. Yet the revelation of this reason for Biff's bitterness is not the only example in this segment of how Willy has carelessly ruined the lives of those around him. Willy has ruined the reputation of the Woman, but can offer nothing to her in return. Despite the promises that he has made to her, he denies and discards her. This parallels Willy's earlier insistence that Linda should not mend stockings. Stockings serve as a symbol of what Willy can provide and as a measure of his success.