Throughout the play, Willy believes, wholeheartedly, that the way to get ahead in life is to be liked. If you are liked, he believes, success will follow. In fact, being liked is more important than actual ability. At one point he tells his boys that he will be a greater success than Charley because whilst he is "liked," he is not "well liked," in comparison to Willy, who is liked. Note how this creed of Willy's is revealed in the following quote from Act I when he remembers Biff and how he was so popular at high school:
He could be big in no time. My God! Remember how they used to follow him around in high school? When he smiled at one of them their faces lit up. When he walked down the street… [He loses himself in reminiscences.]
It is clear from Happy and Biff and what they say that they, to a certain extent, have swallowed this doctrine of their father's as well, though Happy has done this to a greater extent than his brother. However, increasingly, as the play continues, it becomes clear that this is one of many beliefs that Willy has that are completely erroneous, and based more on his own delusions than reality. This becomes clear through the comparison between Biff and Bernard. Even though Bernard is not popular in school, it is Bernard who has become an immensely successful lawyer and it is Biff who has become, in the words of his father, a "bum." The success of other characters and the failure of Willy and his sons indicates that being "liked" and reputation is not the most important thing in the world. This is something that Biff comes to realise by the end of the play.
Willy has the illusion that he is well-known and well-liked mainly because he knows many people. As a traveling salesman he has to be friendly, amusing, and entertaining. But all of his relationships are strictly business relationships. He only has one real friend in the world. That is his next-door neighbor who sympathizes with him and gives him financial help. As a salesman with cordial acquaintances all over New England, Willy is in danger of losing all of his so-called "friends" at one fell swoop if he loses his job. This happens all the time to people who get fired or who retire. They may come around to the places where they used to be welcomed and find that they are just in the way because the people they are trying to cling to are busy and preoccupied with their business concerns. The same phenomenon is observable when a man who has retired comes back to visit the people in the office where he used to work. He no longer speaks the same language as those who are still hustling to earn their livings. Typically, this retiree will sit there for a little while and then get up and leave, never to come back, even if he worked in that place for half his life.