Which is something that happened in willys past?

In Arthur Miller's play "Death of a Salesman," Willy Loman's past is marked by his fleeting success as a salesman and his idealized vision of the American Dream. He often reflects on his earlier days when he was more optimistic and had a promising career, particularly recalling his relationships with his sons, Biff and Happy. Willy's memories are tinged with regret, especially surrounding his failure to instill a strong sense of self-worth and ambition in Biff, which ultimately leads to his tragic downfall. His past is a blend of missed opportunities and the disillusionment that follows his unfulfilled aspirations.