“Losers quit when they’re tired; winners quit when they’ve won”

“Losers quit when they’re tired; winners quit when they’ve won” is a motivational saying that has been printed on many posters. Authorship of the saying is not known.
 
“Losers quit when they’re tired. Winners quit when they’ve won” has been cited in print since at least 1996, when it was printed on a T-shirt. “Losers quit when they get tired; winners quit when they win” is another form of the saying.
 
           
3 July 1996, The Post-Standard (Syracuse, NY), “Right in Tune” by Jeff Theodore, pg. B-1. cols. 3-4:
And 14-year-old clarinet player Jasmine Case’s shirt read: “Losers quit when they’re tired. Winners quit when they’ve won.”
 
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Doug Allen
4/24/97
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Doug Allen
“Losers quit when they’re tired, Winners quit when they’ve won.”
 
Google Groups: rec.sport.officiating   
An umpire’s perspective on the NAFA World Series
Steven M. WIlson
9/2/98
(...)
For me, both the story of Roger Hawes and that of the North Fredricksburgh Express epitomize a sports aphorism: “Losers quit when they’re tired; Winners quit when they’ve WON.” 
 
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November 2001, Cincinnati magazine, “Who Do We Appreciate?” by Linda Vaccariello, pg. 64, col. 2:
And they have clearly cornered the market on affirmation. They are Positive! Upbeat! Winners!
 
Or at the very least, their T-shirts are.
 
“Losers quit when they’re tired; winners quit when they’ve won!” proclaim the shirts of one cluster of parents.
 
11 June 2004, Rockford (IL) Register Star,“Mayfield could make his move at Pocono Raceway” (Gannett News Service), pg. 4E, col. 4:
“I believe in fighting until the end,” he (Jeremy Mayfield—ed.) said in response to a question about his motto of “Losers quit when they get tired. Winners quit when they win.”
 
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Losers quit when they’re tired.  Winners quit when they’ve won. -Unknown
8:39 AM - 14 Apr 2014