Logos are Graphical Extension of the Internal Realities of a Company - Saul Bass
Just like Leonardo da Vinci I believe in Simplicity is the ultimate sophistication. Having said that, simplicity need not be unintelligent, boring or dull. The beauty of a great logo design is that it's Intelligent yet Simple, Complex yet not Complicated, Vibrant but not Overwhelming. The concept of a great logo must be vocal in representation of the business but must not be too rigid.