The Mnemonic Effect in Advertising 

This effect results in the way the brain works, when viewing any advertisement.

The less relevant the message is to the viewer, the more likely it is for him to start thinking of the products or services he is already using.

This might create a buying decision, but not the one the advertiser is expecting.

Advertising incorrectly can actually stimulates the sales of the advertisers competition.

E.g. Your driving your car and hear a pizza commercial on the radio.

You might think of the advertiser, but if you know this commercial your more likely to ask yourself if your hungry, then if you feel like pizza, and if so, then you'll probably order pizza from your favorite pizza place, which might not be the one that is advertised.

In the end you might even end up buying a burger instead. In this case the commercial just reminded you that you were hungary.

And this is how the mnemonic effect in advertising works

The Mnemonic Effect in Advertising by hqq August 5, 2012