Who came up with the saying the customer is always right?
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Who from London came up with the saying the customer is always right?
Harry Gordon Selfridge Harry Gordon Selfridge, Sr.
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Who from Philadelphia came up with the saying the customer is always right?
John Wanamaker
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Who from New York City came up with the saying the customer is always right?
Marshall Field
The customer is always right (disambiguation)
https://en.wikipedia.org/wiki/The%20customer%20is%20always%20right%20%28disambiguation%29
The customer is always right
https://en.wikipedia.org/wiki/The%20customer%20is%20always%20right
"The customer is always right" is a motto or slogan which exhorts service staff to give a high priority to customer satisfaction. It was popularised by pioneering and successful retailers such as Harry Gordon Selfridge, John Wanamaker and Marshall Field. 
The customer is always right
Harry Gordon Selfridge, Sr. (11 January 1858 – 8 May 1947)[1][3] was an American-British[3] retail magnate who founded the London-based department store Selfridges. 
Harry Gordon Selfridge
John Wanamaker (July 11, 1838 – December 12, 1922) was an American merchant and religious, civic and political figure, considered by some to be a proponent of advertising and a "pioneer in marketing".[1] He was born in Philadelphia, Pennsylvania, and served as U.S. Postmaster General during the term of U.S. President Benjamin Harrison from 1889 to 1893.
John Wanamaker
Marshall Field (August 18, 1834 – January 16, 1906) was an American entrepreneur and the founder of Marshall Field and Company, the Chicago-based department stores. 
Marshall Field
"The customer is always right" is a motto or slogan which exhorts service staff to give a high priority to customer satisfaction. It was popularised by pioneering and successful retailers such as Harry Gordon Selfridge who founded the London-based department store Selfridges, Philadelphia native John Wanamaker and Marshall Field and Company founder Marshall Field. 