“A happy customer tells a friend; an unhappy customer tells the world”

“A happy customer tells a friend; an unhappy customer tells the world” is an old business adage. A happy (or satisfied) customer often doesn’t say anything or tells just a few friends, but an unhappy (or dissatisifed) customer tells many more people to warn them. The exact words (and number of people told) vary, but the adage became popular in the mid-1980s, when the American Management Association conducted a business study of the phenomenon.
 
The internet has magnified the adage with a greater number of people hearing from the unhappy/dissatisfied customer (who can effectively complain on websites).
 
   
12 August 1984, Roswell (NM) Daily Record, ‘Shopper important to business person,” pg. 34, col. 3:
A happy customer tells 12 other potential customers. An unhappy customer tells 24, twice as many.
   
Google Books
December 1984, Cincinnati Magazine, pg. 15, col. 2:
“A satisfied customer may not talk, but an unhappy customer will tell ten people.”
   
Google Books
Marketing in Canada:
A management perspective
By René Y Darmon, Michel Laroche and John V Petrof
New York, NY: McGraw-Hill Ryerson
1985
Pg. 680:
The American Management Association found that a satisfied customer tells three people about a good experience while a dissatisfied one complains to eleven.
     
14 June 1986, San Jose (CA) Mercury News, “Informed public wields clout with manufacturers,” pg. 3C:
Studies show that a dissatisfied customer tells an average of 11 people about the problem while a happy customer tells only three people.
 
Google Books
Statistical Process Control:
An IFS executive briefing
By John Mortimer
New York, NY: Springer-Verlag
1988
Pg. 24:
Feigenbaum, in a recent issue of Quality Progress, estimated that while a happy customer tells eight others, an unhappy one tells 22 others!
     
17 October 1989, Deseret News (Salt Lake City, UT), “Companies need consumer service”:
A happy customer will tell three to four people but an unhappy one will tell 11 to 20.
 
23 October 1989, Washington (DC) Post, “The selling of the satisfied customer” by Warren Brown, pg. F1:
According to Goodman’s research, an angry customer tends to tell twice as many people about an unpleasant experience as a happy customer tells about good one.
 
13 March 1990, Roanoke (VA) Times, “Optical superstores oversaturate market,” pg. E1:
A happy customer will tell two or three people. An unhappy customer will tell everybody he sees.
 
Google Books
How to start and run your own bed & breakfast inn
By Ripley Hotch and Carl A Glassman
Harrisburg, PA: Stackpole Books
1992
Pg. 89:
The old sales law is true: A happy customer will tell one or two other people; an unhappy one will tell ...
   
Thinking Aloud
Monday, November 14, 2005
Is the Customer Always Right?
Selling Skills for Non-Salespeople
by Janet Ryan
(...)
We’ve all heard the claim that a happy customer tells 5 friends and an unhappy customer tells 100.
 
Free The Drones Personal Finance Blog
The Internet – Magnifying the Old Rule That One Unhappy Customer Tells Ten People
13 August 2006
   
Social Email Marketing
Apr 13, 2010
Joseph Jaffe: “an unhappy customer will tell a million of their closest strangers”
(...)
The key takeaway here, however, is, and I quote “The old marketing adage is that a satisfied customer will tell 5-7 of their friends about their experience, whereas the dissatisfied customer will tell 15-20. Today, an unhappy customer will tell a million of their closest strangers.”