Sales copy succeeds, in large part, because of omission.
For instance, you don't sell Florida vacations by talking about the humidity. You don't sell white sand beaches by talking about the taste of sea water in your mouth when you go swimming. And you don't sell amusement parks by talking about the long lines.
These details are left out... most of the time.
Of course, there's the "damaging admission"--where you confess a flaw about your product to build trust with your prospect. Most of the time, these admissions don't address any real problem with the product or service being sold. The admission is a decoy... a straw man.
Sometimes damaging admissions are genuine. When they are, prospects respond.
One reason John E. Powers was so successful was his unusual candor. He lived from 1837-1919 and wrote many ads for the Wanamaker's department store in Pittsburgh.
Powers' ads were often so brutally honest that his employer objected to running them. Anyway, at one point, Wanamaker's needed a huge sum of money to avoid closing the store. Powers wrote this:
"We are bankrupt. We owe $125,000 more than we can pay, and this announcement will bring our creditors down on our necks. But if you come and *buy* tomorrow, we shall have the money to meet them. If not, we shall go to the wall."
People flooded the store, bought arm loads of merchandise, and saved the business.
In a separate ad for a different merchant, Powers wrote:
"We have a lot of rotten gossamers and things we want to get rid of."
This sold out the entire inventory of gossamers within hours.
So, yes, copywriting is largely a job of omission, but not always. What would an average copywriter omit... that a world-class copywriter would not? How can you use a damaging admission to make your copy irresistibly persuasive?