If you are a small business and properly using two-step advertising that is uniquely trackable, which, if you are reading this blog you should be, please never listen to the advertising salesperson’s line that 3, 7, 27 or 263 exposures are needed before someone will act on the advertisement. If your first advertisement didn’t at least bring in 2 times the cost of the advertisement the first time, please DO NOT run it again!
Yes, there are elements of branding or “Image Advertising” that do indeed work if you can afford a few thousand impressions. However, if you are reading this blog I will assume that you do not have a 6 figure advertising budget which is what it requires to do effective ‘branding’ in a only a very limited area.
An advertisement medium might be worth running again if you get either a high call rate with a low close rate or vice versa, but with modified copy or design that better addresses the audience in that medium. Both of those can indicate that the medium is right but the message is a bit wrong.
Also- keep in mind that advertisments can get old quickly. If you run the same ad past 5-20 imperessions, be prepared for a slowdown in sales as you have reached most of the audience ready to respond to that particular offer.