Whenever anyone asks me what marketing books I recommend that will help them sell more and learn about the psychology of selling, the first one I point them to is Influence by Robert Cialdini, published in 1984. Then I recommend reading his book Pre-Suasion, published in 2016.
A professor of the psychology of selling and marketing, Cialdini lays out seven ways you can get people to say yes to what you're asking. Anyone who sells things for a living, online or offline, should know and live these seven principles in sales psychology.
Psychology of selling: Cialdini’s seven principles
The principle of reciprocity in sales psychology means that when someone gives us something, we feel compelled to give something back in return. Have you ever gone to Costco and ended up with an unplanned sausage purchase because you felt an obligation to buy after you tried a free sample? That was the principle of reciprocity in action.
Of course, online retailers can’t personally visit the house of each person who interacts with them to shove a sample in their hand. So how can you make reciprocity work for you?
Free gift with purchase
You might not be able to offer something in advance, but you can definitely offer something alongside. This tactic is a favorite of cosmetic and beauty products, demonstrated below by Ulta Beauty.
Even if you don’t advertise the gift in advance, slipping samples of other products into your shipped product is a sales psychology technique that can encourage repeat purchases.
The gift of content
Content is an effective way for online retailers to provide value to potential customers. It’s a different way of providing a gift to your customers. For example, skincare brand Murad taps into the psychology of shopping by providing users with a fun quiz to reach recommendations for the face cleanser that matches their skin type and preferences.
True & Co, an online lingerie retailer, taps into the psychology of buying by helping women figure out the right size and style of bra for them.
Whether it’s a guide for how to make the perfect vinaigrette or an exclusive author interview, use content as an ethical bribe that makes people feel grateful towards your business.
Surprise and delight
While advertising free gifts pre-purchase is a great way to drive first-time purchases and tap into the psychology of shopping, you can take a more subliminal approach to using free gifts to drive online sales. A surprise and delight approach to this tactic in the psychology of selling means that you don’t tell customers ahead of time about what they’re getting for free. Instead, they’ll find out when they receive the product that you’ve thrown in an extra freebie.
Another cosmetics and skincare brand, LUSH, uses this approach frequently. They’ll toss in a free related product. Not only does this help drive repeat purchases and word of mouth, but it also introduces customers to new products that they otherwise may not have discovered.
2. Commitment and consistency
As it relates to the psychology of selling, the principle of commitment and consistency says that people will go to great lengths to appear consistent in their words and actions, even to the extent of doing things that are basically irrational.
That’s why if you’re trying to make a change in your life (losing weight, for example) it can be very helpful to share your goal. Once you’ve committed publicly, you’ll have much more incentive to keep up your end of the bargain.
As a retailer, if you can understand the psychology of buying and get customers to make a small commitment to your brand—like signing up for your email newsletter, they’re more likely to eventually purchase from you. And if you can actually get products in their hand, even if there’s no official commitment to buy them, your chances increase even more.
This is the principle behind Warby Parker’s Home Try-On Program.
Warby Parker knows that with a product that sits in your line of vision all day (literally), look and fit are important. They also know that if they can get a set of frames in your hands, they're a majority of the way toward making a sale, that’s the power of understanding the psychology of shopping.
So they make it as frictionless as possible: Order the samples, get the box, order the frames you want, and send the box back for free. They say there's no commitment, but they're wise students of Cialdini. They know the customer feels the commitment the minute they open the box.
Make it easy to commit with easy returns
You can apply the commitment and consistency principle to your returns policy, too. In one study conducted by Narvar, nearly three-quarters of consumers said they’d would be more likely to buy from a company that has a “no questions asked” returns policy.
Zappos’ and REI are two brands with famously easy return policies that are great examples of this. There's less friction for the customer to buy because they know that if they don’t like it, they can easily return it. But once they have the product in their hands, will they really return it? Maybe not. They're already committed.
The principle of liking as it pertains to the psychology of buying says we're more likely to say yes to a request if we feel a connection to the person making it. That’s why the associate handing out sausage samples at Costco usually has a smile.
It’s also why brands hire celebrities to endorse their products: so that people will transfer their love of Roger Federer to the watches he’s endorsing. Online sunglass brand Prive Revaux uses this as a main principle in their business. They partner with celebrities to create lines for their brand. Fans of the celebs become fans of the sunglasses. There are lots of ways to make this principle work for your store:
Tell your story
If there’s one place that branding is essential for the psychology of selling, it’s in triggering the principle of liking.
Every element of your store (colors, fonts, photo styles, copy, etc.) contributes to your brand identity. Your goal is to create a personality that’s cohesive and that your target customer will like. This might be brisk and efficient if you’re selling into a business market, warm and playful if you’re selling children’s products, or 'earth-mothery' if you’re selling natural products.
And one from jewelry designer Elva Fields:
This is a great way to sum up your story and to get people to like you.
Use relatable models
If you’re selling clothing, jewelry or accessories, one quick way to create a connection to your customer is to show your stuff on people they’ll identify with and like. This doesn’t mean you need to book supermodels; it’s best if they look like your customers. This might mean funky and cool, like Shop Fiercely:
Casual and athletic, like Title Nine:
Or bright and preppy, like Southern Marsh:
Include social links on product pages
People are more likely to purchase something if it’s recommended to them by someone they know and trust. Make sure your product pages have links to Twitter, Facebook, and Pinterest so your customers can easily tell their friends about the great product they found on your site.
Sustainable goods brand United By Blue is doing it right:
And so is Fab:
Display what others are interested in
Have you ever mentally saluted someone’s taste who was wearing the same shoes or shirt as you? You probably felt a quick connection with that person based solely on that one commonality.
Stores can play off that idea by presenting products that are similar to what the person is browsing. Amazon is famous for this approach. They have two ways in which they show which other products are popular among shoppers.
They display which other products customers frequently purchased in the same transaction.
And they also share which other products customers researched during their buying process.
In researching the psychology of selling, you may have heard of the famous Halo effect. Essentially, it’s like the adage, “you are the company you keep.” When your brand evokes something familiar, such as a celebrity, industry expert or even a memory, people will believe that your brand possesses similar qualities to said familiar entity. They’ve established expertise in the space, and you can reap the benefits by associating your brand with authoritative figures, thus inheriting your own sense of authority.
People appear hard-wired to respond to authority (or the appearance of authority). How can you use this to sell?
Is your product hand-crafted by trained artisans? Tell the world all about them like DODOcase.
Books are another great example of this. Are you more likely to buy a run-of-the-mill book about how to cook French food or one by Jacques Pepin? Cookbook Village knows that big names sell books, and they have a whole section for cookbooks authored and autographed by big-name chefs.
These days, the range of products available to a shopper are so vast it’s hard to wade through them all. And that’s why “curation” continues to be an industry buzzword.
Do you have a chief stylist? Create a page with their top picks for the season. Selling fitness products? Have a personal trainer give their favorite picks. Even a little authority is enough; Kepler’s Books provides recommendations from each of their staff members.
You don’t need to have an expert on staff to establish authority for your store and products. A stamp of approval from an expert in your industry could provide just the authority you need to instill customer confidence and persuade browsers to buy.
Remember when Oprah endorsed Weight Watchers and shared her success story? She was convincing because she had first-hand experience with the products and the results. Weight Watchers even created a dedicated page on their website to share her story and expertise, which helped to establish their authority on the topic.
5. Social proof
Social proof is connected to the principle of liking: Because we’re social creatures, we tend to bias toward things other people already like, whether we know them or not. Anything that shows the popularity of your site and your products can be a psychological trigger. According to Nielsen, 83% of consumers trust product recommendations from their friends and family, which is way more credible than anything you can say about yourself.
One approach to using social proof is to provide a “Best Sellers” or “Most Popular” page, as demonstrated by Maple Holistics below. By highlighting that this shampoo is a top seller, Maple Holistics has given it a sheen of desirability.
And of course, ratings and reviews, a la Amazon and countless other retailers, are another useful way to show social proof.
Using social media for social proof
Social proof psychology can also happen off your website, such as on social media. Influencer marketing has become commonplace in ecommerce. Those online comments about your brand and products could generate interest and, in turn, sales. In studying the motivations and psychology of buying, Nielsen also found that two-thirds of consumers trust others’ opinions that are posted online.
Hello Fresh is one brand that uses influencers to establish social proof for their product. Search Instagram, and you’ll quickly see a long list of celebrities and influencers who endorse the brand.
Hi friends! Who has tried HelloFresh?! I've always heard such great things about it but had not tried it until the last couple of weeks. My box arrived on a Monday and we then enjoyed a full week of meals! I was really impressed with how well everything was packed and how fresh everything was. @HelloFresh takes the guessing out of cooking, which I love. I didn't have to plan for the week because @HelloFresh did it for me. As a busy family on the go...the preplanned, prepackaged meal and easy instructions made my life a lot easier! ___________________________ I highly recommend that you try at least a week of these delicious easy to prepare meals for you and your family. @HelloFresh is so kind to offer all of you a discount of 50% OFF your first full week with code: KBSTYLED! Just click on the link in my bio to get started...its super simple! _____________________________ Let me know if you decide to give it a try and what you think! #HelloFresh #HelloFreshPics #FreshFriends #GetCooking #HelloFreshPartner // PC @chelsearoc
Cialdini’s final principle is the principle of scarcity, which states that people are motivated by the thought that they might miss out on an opportunity. Call it the Eternal Teenager Principle: If someone tells you that you can’t have it, you may want it even more.
Announcing scarcity only gets you half of the way there, however. You need to give your audience enough information to act on the opportunity. A simple “we only have 10 left!” message and no obvious path to purchase the product would do a disservice to your message and cause needless frustration.
Sales that are ending
The example below from Style Hunter shows a countdown for how long the product will be available at the discounted price.
Impending out-of-stock announcements
Items about to be taken off of shelves have an element of scarcity built in. As the ModMom example below showcases, if a product is a sample sale or being discontinued, it may be worth highlighting that fact so interested customers don’t miss out.
Seasonal or limited products
Every March when my friend gets her green Shamrock Shake from McDonald’s, she crows with happiness all over social media. She wouldn’t be nearly as excited if she could walk in and get it any time—the knowledge that supply is limited motivates her and creates a thrill around exclusivity.
That’s exactly how I feel about my Pumpkin Spice Latte from Starbucks, and they know other customers feel the same way.
This seventh principle behind the psychology of selling is from Cialdini’s Pre-Suasion.
The principle of unity is based on the idea of shared identities. Your brand and your customers may have shared ideas or values, but unity takes it a step further with identities, or groups. Identities are based upon those commonalities.
Let’s take a scenario: You might be a brand that sells outdoor gear to customers who love spending time outside. When you apply the unity principle, you’re identifying with groups of outdoors lovers. Patagonia is a prime example of a brand that has done this. They’ve self-identified not only as lovers of the outdoors, but as activists who are fighting to preserve the outdoors. This has encouraged groups of customers who share that identify to have fierce loyalty to the brand.
Don’t be afraid of labels
When applying the unity sales technique to your online store, it’s okay to use labels. In fact, it’s encouraged. Labels enforce these shared identities. You’re not a “Justin Bieber fan,” you’re a “Belieber.” There’s a reason his fans are so fiercely loyal; and they share that identity with each other to create an entire community of passionate Beliebers.
Ecommerce brands can take a similar approach. If your customers have created a label on their own, embrace it. If they haven’t, look for opportunities to do so. The label can revolve around your brand or around a shared value.
Don’t be afraid of enemies
Sharing enemies can be an effective sales psychology technique and quick way to build unity with your customers. The age-old battle between Apple and Microsoft is a prime example of this. The advertising war between the two major brands have fueled the rivalry, not only between the companies themselves but also among their customers. Mac and iPhone users are fiercely loyal to the brand and will quickly denounce all things Microsoft, and the same rings true the other way around.
But your nemesis doesn’t have to be serious. Chubbies Shorts, for example, has waged war on pants and business attire. Their customers have found unity with the brand thanks to their shared dislike of conforming pants wear. They’ve created tongue-in-cheek marketing campaigns that have established that unity with their customers.
Don’t be afraid to take a stand
Increasingly, consumers are rewarding brands that take a stand politically, socially or environmentally with their wallets. One Sprout Social survey found that two-thirds of consumers actually want brands to publicly announce their stance on important issues.
Looking back at Patagonia again, the brand was certainly not shy to speak out against the American government when public land from the Bears Ears National Monument was taken away. They even published a blog post on their website dedicated to the movement.
While this move may have turned off a lot of potential customers, it strengthened the connection with the customers who have the shared identity of environmental activists. And those customers are likely more aligned to their target anyway.
But what about pricing?
You may be wondering where the extremely common retail tactics of sales and discounts fall under these seven principles. Is Cialdini saying that price doesn’t impact people’s purchasing behavior and isn’t a viable sales psychology technique?
Not so. In fact, Cialdini mentions a couple of pricing experiments in the beginning of his book. But think of it this way: The price of your product represents the size of a risk someone is going to take on. In other words, people will be a lot more choosy over a $10,000 product than one that is $1.
The seven principles of influence represent additional non-obvious ways to impact perceived risk. For example, by using appeals to authority, you're decreasing the risk of a 'yes.’ Someone who says yes (to your appeal to buy a product) can always point to the authority you've demonstrated to rationalize their purchase. With scarcity, there is an inherent increase in the risk of a 'no.' Someone who declines an offer now might miss out down the line.
So given a price you’ve settled on for your products, using the principles of influence can decrease the risk of 'yes' (liking, social proof, authority, unity) or increase the risk of 'no' (scarcity, consistency, reciprocity).
Sprinkle these sales psychology techniques throughout your site and watch your sales go up!
About the author: Beth Morgan is the COO of Twine Data and former VP of Operations at Red Bricks Media. She has been working in and around startups for over 20 years.
An earlier version of this article was originally published in September 2013.