Willy Loman is a traveling salesman that playing the roles of father and husband in the whole family. There are lots of facts to prove that he always talked without making the decision. The crucial fact that profoundly impacts his decision is his unrealistic dream from Ben, and also the memory from the past on his own. Undoubtedly, there are several facts that he has infidelity to both his sons and his wife. The relationship between each other in Loman's family is bad due to Willy's wrong beings. There are some good evidences to show that Willy didn't have father's obligation to teach his sons well in a right track.
First of all, during the past of their life, Willy commanded to his sons "Boys! Go right over to where they're building the apartment house and get some sand."P.50 Willy told his sons to steal some sand. Under such circumstance, I think Willy should be blamed on his wrong being, because at the mean time, not only Charley did warn him few times that the watchman will put the cops on him, but also Linda objected to let Biff to do so.
However, Willy ignored them and even said, "I gave them hell, understand."P.50 Willy definitely is a mean father without considered other's feeling. Also, it shows he always does something or made a decision without thinking. Moreover, related to the stealing from his son - Biff. A case that Willy was talking to Biff and to get to know about how did he get the new football. "I want you to return that"P.30 and "Coach'll probably congratulate you on your initiative!"P.30 When Willy knew Biff stole the football, he just told him to return that, but after that, he even praised him he has the supported by the Coach.