The Question and Answer section for Death of a Salesman is a great resource to ask questions, find answers, and discuss the novel.
Willy tries hard or at least thinks that he tries hard. Willy is such an unreliable character that it is difficult to gauge exactly how hard he works for the company. He fails to be profitable for the company and is eventually fired. I would...
Willy did not contribute much to the company. Willy is delusional and thinks he does but the company eventually lets him go.
In Act I, Scene III, when Linda asks Willy how much he made on his sales trip, Willy tells her that he sold $1200 worth of goods, which would give him a commission of around $200. A few minutes later his claim is reduced drastically.