American journalist Sydney J. Harris (1917-1986) wrote a “Strictly Personal” column in January 1967 that was titled, “How to tell a Winner from a Loser.” A popular line is: “A winner makes commitments. A loser makes promises.” The line has been used in business and in sports, although Harris is almost never credited.
 
“A gentleman makes commitments. A loser makes promises” is a variation that was posted on Twitter on November 12, 2011. The saying has been printed on many images.
 
 
Wikipedia: Sydney J. Harris
Sydney J. Harris (September 14, 1917 – December 7, 1986) was an American journalist for the Chicago Daily News and, later, the Chicago Sun-Times. He wrote 11 books and his weekday column, “Strictly Personal,” was syndicated in approximately 200 newspapers throughout the United States and Canada.
 
9 January 1967, New Castle (PA) News, “Strictly Personal” by Sydney J. Harris, pg. 4, col. 6:
How to tell a Winner from a Loser:
A winner says, “Let’s find out”; a loser says, “Nobody knows.”
 
When a winner makes a mistake, he says, “I was wrong”; when a loser makes a mistake, he says, “It wasn’t my fault.”
 
A winner credits his “good luck” for winning—even though it isn’t good luck; a loser blames his “bad luck” for losing—even though it isn;t bad luck.
 
A winner knows how and when to say “Yes” and “No”; a loser says, “Yes, but” and “Perhaps not” at the wrong times, for the wrong reasons.
 
A winner isn’t nearly as afraid of losing as a loser is secretly afraid of winning.
 
A winner works harder than a loser, and has more time; a loser is always “too busy” to do what is necessary.
 
A winner goes through a problem; a loser goes around it, and never gets past it.
 
A winner makes commitments; a loser makes promises.
   
Google Books
Leaving the Surface
By Sydney J. Harris
Boston, MA: Houghton Mifflin
1968
Pg. 100:
A winner makes commitments; a loser makes promises.
 
4 February 1985, Philadelphia (PA) Inquirer, “Citizenship: The Young Marines Learn Respect, Discipline” by Kurt Pfitzer, pg. H20:
New members are issued a guide book that, among other things, defines positive and negative attitudes in a section titled “Winners and Losers.” Some examples:
 
“A winner makes commitments; a loser makes promises.”
 
Google Books
The Mental Game of Baseball:
A Guide to Peak Performance
By H. A. Dorfman and Karl Kuehl
Lanham, MD: Diamond Communications
1989
Pg. 264:
A Winner makes commitments. A Loser makes promises.
   
4 January 1990, Orlando (FL) Sentinel “Forget the Calendar: Workouts Set for 6 Spring Sports on Wednesday” by Frank Carroll, pg. 5:
A winner makes commitments.
A loser makes promises.
 
Google Books
Ponders, Proverbs & Principles
By Rodney R. Weckworth
Roseville, CA: Publishers Design Group
2005
Pg. 89:
A winner makes commitments; a loser makes promises.
 
Google Books
10 Essentials for High Performance Quality in the 21st Century
By Diomidis H. Stamatis
Baca Raton, FL: CRC Press
2012
Pg. 277:
A winner makes commitments.
A loser makes promises.
 
Twitter
Alexander Wright‏
@ObsessedBeyStan
A gentleman makes commitments… A loser makes promises!
12:09 AM - 12 Nov 2011
 
Twitter
World Connection‏
@1WCUK
A gentleman makes commitments… A loser makes promises….
4:26 AM - 12 Nov 2011
 
Google Books
Idiot’s Guides:
Management Skills
By David Rohlander
New York, NY: Alpha Books
2014
Pg. 100:
A winner makes commitments; a loser makes promises.