“A business with no sign is a sign of no business”

Many sign companies have advertised themselves with a popular slogan. “A business with no sign is a sign of no business” was cited in print in April 1959. “A business without a sign is a sign of no business” was cited in print in June 1959.
   
 
SBA.gov (The U.S. Small Business Administration)
Why do I need a sign for my business?
Answer:
There are many reasons, the most primary of these being:
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. Many merchants increase their business measurably just by adding a good sign. Conversely, many have gone out of business because they simply were not identified well, so not enough potential customers knew of their existence. As one sign industry professional put it, “A business without a sign is a sign of no business.”
     
17 April 1959, Galesburg (IL) Register-Mail, pg. 14, col. 8 ad:
“A business with no sign
Is a sign of no business”
DEL HOWARD SIGNS
1576 Monmouth Blvd.
 
22 June 1959, Manitowoc (WI) Herald-Times, pg. T-9, col. 2 ad:
Signs
CONFUCIOUS SAYS:
“A business without a sign, is a sign of no business.”
H. R. AGGEN
2507 Marshall Street
CUSTOM MADE SIGNS
 
30 January 1963, Clovis (NM) News-Journal, pg. 8, col. 3 ad:
A BUSINESS WITHOUT A SIGN IS A SIGN OF NO BUSINESS
CLOVIS SIGN SERVICE
 
3 November 1964, Gettysburg (PA) Times, pg. 2, col. 7 ad:
SIGNS
“A BUSINESS WITHOUT A SIGN IS A SIGN OF NO BUSINESS”
JOSPEH A. REAVER
   
Google News Archive
5 May 1970, Sarasota (FL) Herald-Tribune, pg. 4-B, col. 2:
Self Advertising
MADISONVILLE, Ky. (AP)—A local sign painter advertises his own trade with the sign painted on his pickup truck which reads: “A business with NO SIGN is a sign of NO BUSINESS.”
 
Google News Archive
20 December 1973, Dayton (OR) Tribune, “Pacific Reflex Signs,” pg. 3, col. 3:
“A business with no sign is a sign of No Business.”
 
Google News Archive
28 August 1980, Sarasota (FL) Journal, ‘Cope’s Column” by Bill Copeland, pg. 9-A, col. 3:
Del Bixler spotted this company’s sign near Clearwater—“A Business With No Sign Is A Sign Of No Business.”
 
Google Books
Entrepreneurship:
An Introduction
By Albin Bowler
Cape Town: Nasou
1995
Pg. 82:
The business must also be visible with clear signs. Remember: ‘A business without a sign, is a sign of no business.’
 
WINK-TV (Southwest FL)
Bonita Springs proposes sign ordinance
Published: Sep 04, 2014 6:49 PM EDT
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Bill Wallace knows a good sign when he sees one. He’s been in the street-side advertising business in Southwest Florida since the 1960s. “There’s an old adage, a business with no sign is a sign of no business. Or a sign of no business is a business without a sign,” said Wallace.