Brands are machines for delivering quality earnings at high margins

Write a 3000-4000 word essay on the following topic:

"Brands are machines for delivering quality earnings at high margins"

A good answer would begin by explaining the concept of the brand and outlining reasons why people are prepared to pay a premium for strongly branded products and services. You might also explain how the concept has evolved from its origins in the late nineteenth century to the present day. You should give some examples of strong brands and explain the source of their strength.