“Hope is your worst enemy in the market”

“Hope is your worst enemy in the market” is a rule in A Treasury of Wall Street Wisdom (1966), by Harry D. Schultz and Samson Coslow. Many investors see stocks go down, but don’t sell them (hoping that the stocks will go back up again).
 
A similar phrase (used by opponents of Barack Obama’s 2008 “hope”-themed presidential run) is “hope is not a strategy.” A similar Wall Street “hope” phrase is “hope is a lousy hedge.”
 
   
Google Books
A treasury of Wall Street wisdom
By Harry D. Schultz and Samson Coslow
Palisades Park, NJ: Investors’ Press
1966
Pg. 197:
Rule 5. Do not be overly optimistic and let your prospective profits to run away with you, hoping that stocks will go up still further. Hope is your worst enemy in the market. The public usually observes its stocks dropping, hoping against hope that they will advance or make a comeback. But this rarely happens soon enough.
   
Talk and Share
Ben
2 Years, 1 Month ago  
Stock Market Wisdom
Hope is your worst enemy in a bear market. When things go bad, it is human nature to hope that they will improve.
     
Bleacher Report
NFL Draft 2010 Aftermath: Can’t You Just Feel Hope For the Tampa Bay Buccaneers?
by Tom Edrington
Written on April 25, 2010
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An old Wall Street saying goes:  “Hope is your worst enemy in the marketplace.”