Who is the best logo designer of all time?

Paul Rand (born Peretz Rosenbaum, August 15, 1914 – November 26, 1996) was an American graphic designer, best known for his corporate logo designs, including the logos for IBM, UPS, Enron, Westinghouse, ABC, and Steve Jobs's NeXT.
He was one of the originators of the Swiss Style of graphic design.
From Wikipedia.

Have you heard about the Doodle team? Doodle originated from the caps of Larry and Sergey, the Google Founders.
It was Dennis Hwang who was appointed to create Google special day logo's termed as doodle in Google company.
Now the world best logo concept designers belong to Google and the team is named Doodlers or Doodle engineers.
I just love the art and concept they bring in their Google logo for every events, birthdays and a whole lot more.

You can google this question and you will find all history about logo designer, I am working in logo designing company and I have designed more than 3000 logos.
may be this is not answer of your question but searching is best for knowledge.

Paul Rand (born Peretz Rosenbaum, August 15, 1914 – November 26, 1996) was an American graphic designer, best known for his corporate logo designs, including the logos for IBM, UPS, Enron, Westinghouse, ABC, and Steve Jobs's NeXT.
He was one of the originators of the Swiss Style of graphic design.
From Wikipedia.