A logo design is basically to communicate a business message to the viewers. If a logo has successfully taken the message to the targeted customers, such a logo design will contribute immensely towards growth of a company and its business.
If you take a good look at famous logos, you will notice that they all are created in a simple way with a meaning and purpose behind them. It is due to their simplicity of the design that they can easily convey business message. Simplicity of a design is also responsible for a logo design remaining in the memory of the people.
Besides simplicity, a unique creativity in the form of hidden message in logo is also a contributing factor in its success. A trick in creating hidden message is to incorporate a symbol which is seen to the viewers with little more focusing on the logo. But once the symbol is clear, it is immediately visible every time you see the design. The symbol usually simple.
Famous logos of USA Network, Northwest Airlines, Pepsi, ZIP, Oxfam etc. are some of the examples of simple design. In creating these logos, the designers used few circles and rectangles without putting many other design elements.