What drives a person to buy something? When asked this question, most people respond by claiming that they evaluate the pros and cons of the particular decision at hand, then make their final choice based on sound judgement. Many will go on to add that unlike other people with wavering personalities, they are not easily persuaded and seldom make emotional decisions.

This typical discrepancy is called the actor-observer bias. The tendency to attribute personality-based rationale to the observed behaviors of others, while attributing situational factors to one’s own behavior, is known as the fundamental attribution error (ex. “Sam forgot the conference call because he’s a scatterbrain”, whereas “I forgot the conference call because I was so slammed at work”).

It’s no wonder that anyone in sales, be it of a product or service, is interested in the psychological process involved in making a buying decision. What get’s someone to say “yes, I want that, and I’m going to buy it!” Biases, like the one listed above, are integral to buyers’ decision making process, and should be intentionally integrated into your marketing strategy.

Here are 5 concepts experts have identified as contributing to decision making:

Reciprocity

Reciprocity is an essential psychological element, referring to the desire to give something back after something is given to us. This concept can be incorporated into a marketing scheme by offering potential buyers “something” small and then “asking” for something in return. For example, a website may offer a coupon, discount or free newsletter as a hook, and ask for small things in return (“please join us on Facebook to receive a coupon code”,”please follow us on Twitter and receive 10% off your next purchase”). Although our goal is to convert a visitor to a client, we should also understand and appreciate the value of these preliminary reciprocal relationships.

Commitment

This approach focuses a person’s desire to act in accordance with their expressed beliefs. Simply put, once a person publicly voices support for a product or company, they are more likely to defend and remain loyal to their initial stance. This tendency is most evident on social media sites, and is one of the forces driving the significant shift towards exploiting social media sites as marketing channels.

Social Proof

Also known as Informational Social Influence, social proof is the result of a mental process which occurs in ambiguous social situations. When unable to select the appropriate course of action, people tend to follow the behavior of others around them, who they assume are more knowledgeable about the situation. Examples of how Social proof can be conveyed to a potential client are “153 people ‘like’ this”, “98 people have retweeted this”, “people who looked at this product also looked at…” Psychologically, we react to these “popular” items positively, and assign to them an increased innate value.

Shortage

People are more likely to buy something, if they perceive their opportunity to purchase as being limited by limited availability or time. Examples of the exploitation of this principle, are statements like “offer ending today”, “only 3 left in stock”, “going out of business sale!”. Several mechanisms operate within this principle. A person thinks that if there are only a few left, people must be buying it, therefore it’s a good product (a Social Proof tag-team). Also, people do not want to miss out on the opportunity to buy this product, or buy it at a certain price.

Expertise

A fundamental concept in the consumer persuasion is that behavior is more easily influenced through credible sources. As consumers, we are more likely to follow the advice of someone we perceive as an expert. This notion, drives website designers to include testimonials and references that will be influential for website visitors.