Why does Willy talk about the past to Howard in Death of a Salesman by Arthur Miller? Why does Howard fire Willy?

Willy's
main mission is to try to persuade Howard to let him work locally rather than having to travel
all over New England. Willy would like to convince Howard that he is still a good salesman in
spite of his age. He brings up Dave Singleman for two reasons. One is to show that he is a
dedicated professional salesman who loves his work. He was inspired by meeting
eighty-four-year-old Singleman who was still on the road and was practically legendary. Willy
also uses Singleman to show that age is not necessarily a handicap. Willy is only sixty-three,
and by implication he has another twenty good years left in him. Howard doesn't really believe
him. Willy wouldn't be asking to be taken off the road if he weren't feeling his age. Willy is
just dating himself by bringing up old stories of the days when drummers all traveled by train.
He is showing that he not only looks old but is developing old men's idiosyncrasies, such as
absent-mindedness and looking back at the past. Willy goes from bad to worse by pleading that he
would be willing to get by on less and less if he could only work close to home. That doesn't
sound like the ambitious sort of salesman Howard would want in his company. Employers want men
who still have the American Dream, not men who are losing it. Howard's treatment of Willy is not
as bad as it could be. He never actually says, "You're fired!" He says he's busy. He
says Willy needs a rest. He claims he has no available spot for him locally. All of this is
because Howard does realize that Willy had a close relationship with Howard's father and because
he knows Willy has worked hard for the firm. Howard feels guilty. He isn't exactly snubbing
Willy but trying to ignore him, get rid of him, and forget him. When Willy finally becomes angry
and disrespectful it gives Howard an excellent opportunity to fire him.