Persuasion theory studies the tricks and methods that make advertising effective. For an ad to succeed, people have to pay attention to it, understand the message and remember it later. Advertisers have several techniques for successfully making an ad persuasive.

Source Credibility

An ad may be persuasive not because of what it says but because of who says it. An ad promoting a new supplement or medical treatment may quote a doctor, because doctors are seen as trustworthy and knowledgeable. Other ads rely on ordinary people who use the product, hoping potential buyers will identify with people like themselves.

Distraction

An ad can concentrate the public's attention, or it can distract the audience with music or camerawork. Distraction can be an effective persuasive tool, depending on how strong the ad's message is. If the message is one an individual might normally avoid or reject, distractions make it easier for the message to bypass his resistance. Critics of prescription drug ads on television, for example, have charged that the distracting music and visuals reduce the impact of information about the medication's risks and side effects.

Repetition

Most ads show up in newspapers, on the Internet or on television multiple times. Repeating the message is an important part of advertising's persuasive power. However, repetition also can wear out customer interest, particularly among people such as heavy TV viewers who see the same ads more than the average watcher. Different types of ads hold up differently under constant use. Advertising Age says, for example, that an ad that quotes product users is more effective when repeated than a similar ad that presents the facts without a source.

Benefits to Users

Some ads persuade simply by showing how the product benefits the users. The Advertising Educational Foundation says, for example, that when Procter & Gamble decided to market its Pantene Shampoo worldwide, the company's research found that healthy hair was important to many women. It built its campaign around that benefit — "hair so healthy it shines."

Emotional Appeal

Some ads go for a more emotional appeal than a logical argument. Ads for greeting cards, for instance, don't make a logical case for why you should send someone a birthday card. Instead they emphasize how happy you can make someone feel, or how much closer your relationship will become after doing so.

Laughter

Many ads rely on humor to help sell the product. By providing a comic sketch, the ad can hold the viewer's attention, and also make it easier to remember the ad and the brand's message.