第51页 Those little ladders in your head

Chapter 4．Those little ladders in your head  
According to Harvard psychologist Dr. George A. Miller, the average human mind cannot deal with more than seven units at a time. Which is why seven is a popular number for lists that have to be remembered. Seven-digit phone numbers, the Seven Wonders of the World, seven-card stud, Snow White and the Seven Dwarfs.  
To cope with the product explosion, people have learned to rank products and brands in the mind. Perhaps this can best be visualized by imagining a series of ladders in the mind. On each step is a brand name. And each different ladder represents a different product category. 
A competitor that wants to increase its share of the business must either dislodge the brand above (a task that is usually impossible) or somehow relate its brand to the other company’s position.  
The 7-Up’s uncola position: Cola, Pepsi, and three, 7-Up.  
More than anything else, successful positioning requires consistency. You must keep at it year after year.
The F.W.M.T.S. trap: Forget what made them successful.  
Shortly after the company was sold to ITT, Avis decided it was no longer satisfied with being No. 2. So it ran ads saying, “Avis is going to be No. 1.” However, Avis was not destined to be No. 1 unless it could find a weakness in Hertz to exploit.