"All your products are ephemeral.  Only your customers are real." 
           - Don Peppers 

"When the product is right, you don't have to be a great marketer." 
           - Lee Iococca
 
"A product is, to the potential buyer, a complex cluster of value satisfactions." 
           - Theodore Levitt
 
"No matter how skillful you are, you can't invent a product advantage that doesn't exist.  And if you do, and it's just a gimmick, it's going to fall apart anyway."
           - William Bernbach
 
"The aim of marketing is to know and understand the customer so well that the product or service fits him and sells itself." 
           - Peter Drucker
 
"You cannot sell a doughnut without acknowledging the hole." 
           - Harold Shayler