For instance, if someone meets you and you tell them about your business, you want to know that they can find you in case they lose your information or business card. By having a name that is easy to remember and unique, you have a better chance of them finding your site, company or brand.
Another example is the Kleenex brand. Not only do most people call a tissue a Kleenex, it doesn't matter what brand it is. Other examples include Coke, Vaseline, Jacuzzi and Xerox. All of these are brand names that have become what we know as the item itself.
By creating a brand that people remember, you stay in their minds and that helps your business out by conveying your brand as something they won't forget.