Forever $21$ is developing a program to get to know its customers. Which of the following is NOT a reason why Forever $21$ needs to understand consumer buying behavior?

a$.$ All customers are the same when it comes to buying behavior.

b$.$ A firm should create a marketing mix that satisfies customers.

c$.$ Customers' reactions to marketing strategy can affect the firm's success.

d$.$ The marketing concept stresses that a firm should know its customers.

e$.$ It helps the marketer predict how consumers will respond to marketing strategies.