Let’s face it. We all sometimes buy things we don’t really need, whether it’s a pair of expensive designer jeans, an extra slice of cheesecake, or an upgrade of the smartphone we bought last year. More than just our taste and available income drive those unnecessary acquisitions. Here’s my list of seven psychological reasons why we do it:
1. We’re swayed by marketing.
One of the most frequently mentioned influences on consumer behavior is, of course, marketing. Advertising makes us remember and recognize brands better while also affecting our preferences and perceived needs. It changes our attitudes towards products. Effective advertising doesn’t simply provide rational arguments in favor of a purchase, but works through emotions as well. The most successful ads on the internet—the ones that go viral—are those that trigger the right emotions, such as surprise or amusement.
Marketing designs and packages products to make them more appealing, frames messages in more convincing ways, and sets price promotions that are hard to resist. Did you really plan to get those potato chips or did you just buy them because of the "Buy One Get One Free" offer?
Store managers may also manipulate environmental cues to change our buying behavior. For example, research in a wine store found that people bought more expensive wines when classical music was played in the background than when they heard Top 40 music.
2. We copy other people.
We’re influenced not just by marketing, but also by consumers like us. Sometimes we imitate others to fit in; other times we copy people we know because we’re simply uncertain about the best choice. Our peers play an important part in this process.
But copying others is not limited to the influence of people we know. Simply noticing what other people around us consume can affect what we buy—often unconsciously. This may be as basic as buying an ice cream in the park after seeing others eat some first. The iPhone is another example. Apple works with powerful cues signaling ownership that are apparent even when the phone itself is hidden from view. Have you ever wondered why Apple earphones are still only available in white and why they don’t offer more diversity in generic ring tones?
3. We’re impulsive.
Personality traits affect our behavior, including what we do as consumers. One such trait is impulsiveness. As with any trait, some of us are more impulsive than others. In some cases, this disposition can contribute to problems like ADHD or bipolar disorder, and those of us who tend to make unplanned purchases are considered impulsive buyers. One study found that impulsive buyers tend to react more to external triggers—including advertisements, visual product elements, and promotional gifts—than other consumers.
An important part of the brain related to impulsivity is the striatum, which is activated by stimuli associated with reward. Neuroscience research suggests that simply seeing more attractive product packaging can lead to greater activity in the “reward center” of the brain among impulsive buyers.
What happens once we make that impulse purchase? We rationalize it. Justifying an unnecessary purchase is a skill many of us have come to master very well.
4. We’re tempted by certain products.
Many impulse purchases involve so-called hedonic products, things that give us pleasure or enjoyment. Examples include candy, DVDs, or wine. Another type—which can overlap with hedonics—are symbolic products, goods associated with our self-image—a designer suit, perfume, or a flashy gizmo. Both of these product types are strongly linked to our emotions.
When we think of impulse purchases we don’t usually consider utilitarian or functional items like screwdrivers or cleaning supplies. Naturally, the more practical a product, the easier it is for us to justify that we truly need it in the first place. But while these products are not prime candidates for unplanned purchases, men are more likely than women to buy utilitarian goods on impulse.
5. We succumb to our moods.
Emotions are a major influence on the way we think and act. "Hot states," such as hunger, craving, or arousal, compel us to satisfy our immediate needs, which may occur at the expense of more long-term considerations.
Moods also affect us. When we feel good, we have higher energy levels and like to reward ourselves more generously. We let down our guard to some extent by switching off the more reflective part of our mind in favor of intuition or impulse. In the previously mentioned study on impulse buying, 51 percent of respondents said that “feeling happy” was a trigger for unplanned purchases. Negative feelings can also lead to unnecessary purchases: Among compulsive buyers (people with a repeated urge to buy), a purchase often helps transform a negative affective state, such as depression or sadness, into a positive state.
6. We’re affected by states of mind.
Different states of mind are another factor in moments of consumer decision-making. Some of these relate to our thinking resources. When we are distracted, preoccupied, or under time pressure, our capacity to reflect and deliberate is limited, and we are more likely to be influenced by subtle cues or act on impulse. One famous experiment asked consumers to choose between fruit salad and chocolate. Some subjects also had to memorize a seven-digit number, and 63 percent of them chose the chocolate cake, compared to only 42 percent of those whose processing capacity wasn’t limited. We can expect similar effects when we are mentally depleted (say, after a long day at work), which reduces our ability to control our willpower.
7. We don’t like change.
Human resistance to change commonly takes one of two forms. The first is habit, which is about doing the same thing repeatedly. Buying habits can persist even when needs or preferences change. In my favorite experiment on habit, one group of participants was given fresh popcorn and another group stale popcorn before watching a movie. People also rated their liking of the popcorn and indicated the strength of their usual habit to eat popcorn in movie theaters. Those with strong habits ended up consuming equal amounts, regardless of how stale or fresh it was, and despite the fact that they disliked the stale popcorn. Non-habitual eaters consumed less of the stale variety.
The second type of resistance to change is a more general state of inertia, which is often about inaction (you may call it laziness). This may work to the advantage of companies such as utility providers. Assuming you’re no longer locked into your mobile phone contract, do you really still need to be on the "500 free minutes per month" plan, given that your actual call time has dropped to about 200 minutes?
Available from July 2014: The Behavioral Economics Guide 2014 on BehavioralEconomics.com (free download)