In Death of a Salesman the corporate system is discussed as a sort of machinery which sucks its workers dry and then spits them out whenever they are no longer needed. This is a sort of warning that Miller intends to send out to the audience during a time in history where industries were growing, manufacturing, and selling in mass, thus replacing quality with quantity.It is a sign of the changing times, from when Loman was young, into what the city and his society has become now: a faster, non-stop machine of productivity and speed.
Tracing back Willy's time-line, we could argue that Howard Wagner's father hired Willy during a time when the need for mass sales, and more income was not as big. This is a possibility because, even though Willy once boasted of having a steady clientele, he was still not shooting to be the best, nor was he the best at anything in his company. Hence, we can conclude that Willy's first years in the firm were (too) comfortable, easy-going, and steady.
Once society begins to change, his boss dies, and the company is passed onto the late boss's younger son, Willy is no longer a young man, nor is society a place to find a quality of life. Like society, his firm has changed, from a small and homely company, to what Howard Wagner would want to see become a big business. Willy is therefore way behind because he can no longer produce work, attract a client, move from state to state, or even cross city lines. Willy is as old and useless as the car in which he has been driving for so many years. Therefore, since he is no longer needed, he is let go without any consideration. This is the concept of the corporate system: that you are only one of the many parts of its machinery and, once you break down, you can be easily replaced.