Behavioral economics & viral marketing case studies
































Labour Illusion Details
Labour Illusion means we value a service more when we see the effort behind it, even if that effort doesn’t actually change the result. Visible work feels like higher quality.
Think of a small family business that makes wedding dresses and shows videos of where they source their high-quality fabrics and how every stitch is done by hand. The dress isn’t technically different, but seeing the craft makes it feel more valuable and worth the premium.
In marketing this bias shapes how brands show process, craft, behind-the-scenes steps, or progress bars. When people see the work, they believe the service is better.
Labour Illusion Guide
Labour Illusion Research
In a Harvard experiment, a travel site that visibly showed its search process (scanning airlines, etc.) was preferred by 63% of users even when it took 30-60 seconds longer, versus only 42% preferring a faster site with no visible effort (that's a 50% difference!).
Customers valued the service more when they saw (or believed) more work was being done on their behalf.
Labour Illusion Examples
1. Stetson Cowboy Hats
Stetson openly shows its long, detailed hat-making process of felting, shaping, hand-trimming, and finishing that can take up to four weeks. Customers see photos and videos of artisans molding crowns, cutting brims, and polishing by hand. This visible craftsmanship creates a strong labour illusion, making the hats feel premium, authentic, and worth the high price.
Trollsky, run by Polish knifemaker Michał Sielicki, shows every step of the process: forging, grinding, heat-treating, polishing. Everything is visible through photos and videos. By exposing the dirty hands, sparks, steel, and slow manual work, he creates the feeling that each knife is built from scratch with real effort. This visible labour increases perceived value. Buyers see the knife as a crafted object, not a factory product, which justifies premium pricing and builds strong loyalty.

Guinness is poured in a slow, two-step ritual: pour, wait, top up. The extra time and visible effort make people believe more skill and care went into the beer.
Even though the process could be faster, the visible labour makes the beer feel higher quality and more “crafted".
Veblen Goods Details
Veblen Goods are products people want more when they cost more. The high price doesn’t just signal quality, it creates desire by signaling status.
Think of a limited-edition luxury watch that becomes even more wanted after its price increases. The higher cost makes ownership rarer and more visible, so demand rises instead of falling.
In marketing, this effect appears in categories where status, visibility, and exclusivity matter more than utility. For these products, lowering the price would actually reduce their appeal.
Veblen Goods Guide
Veblen Goods Research
The research from 2018 shows when higher prices increase demand, and when they stop working. The author ran 8 controlled experiments using real luxury products (watches, trench coats, travel bags, champagne). Prices were raised by ~6% (low) and ~11% (high), which matches real luxury pricing (~3-10% per year, confirmed by experts). Results depend entirely on the motivation for why people buy.
Overall conclusion:
Price increases of ~6-11% raise demand only when price clearly signals status or exclusivity. Above this range, the effect often disappears and demand returns to normal (higher price >> lower demand). Price works only as a social signal, not as a cost, quality test, or pleasure tax.
Veblen Goods Examples

1. Hermès Birkin
Birkin bags officially start around $10,000-$12,000, but rare versions resell for $50,000-$500,000+, which only increases demand and status signaling. The difficulty and price make the bag a status symbol. People want it because most people can’t afford it.

Supreme sells basic items (T-shirts, bricks, crowbars) at very high prices. The price itself signals cultural status and insider knowledge. Cheap Supreme would not be Supreme.
Placebo Effect Details
Placebo Effect means our expectations change how we experience a product or outcome. When we believe something will work better, it often feels like it does, even if nothing objectively changed.
Think of taking an expensive painkiller you believe is strong and feeling relief faster, despite it being identical to a cheaper one. The belief shapes the experience.
In marketing this bias shows up in branding, packaging, pricing, and framing. When something looks premium, advanced, or “scientifically proven,” people often experience better results because they expect them.
Goal Gradient Effect Guide
Placebo EffectResearch
In a 2005 study, participants drank the same energy drink, but some were told it cost full price ($1.89) while others were told it was discounted ($0.89).
After 10 minutes, they solved anagram puzzles. The full-price group solved about twice as many puzzles, while the discounted group performed ~50% worse, despite consuming an identical product.
Follow-up analyses showed this happened because a lower price reduced expectations, and those weaker expectations directly reduced performance.
In a separate experiment, people who drank a discounted energy drink reported greater fatigue and worse workout quality than those who believed they paid full price.
The authors concluded that pricing acts as a placebo (or nocebo) - discounts can literally make products work worse by lowering perceived effectiveness, even when the product itself does not change.
Placebo Effect Examples

1. Red Bull
People who believe they drank Red Bull perform better on tests and feel more alert.
The effect comes from expectation, not just caffeine. Branding and messaging amplify the perceived boost.

Painkillers labeled specifically for headaches are perceived as working better for head pain than general pain pills. Even when the formula is the same, the specific promise changes how strong the relief feels. The brain expects better results in that exact spot and often experiences them.

Because people believe Guinness must be poured “the right way,” they expect it to taste better after the ritual. This expectation changes the experience. Drinkers report smoother texture and better taste. The ritual doesn’t just pour the beer, it primes the brain to enjoy it more.
Charm Pricing Details
Charm Pricing means prices ending in 9 or 99 feel cheaper than they really are. Our brain focuses on the first digit and ignores the rest.
Most pricing decisions are intuitive, not analytical. People feel the price before they calculate it. Charm pricing exploits that quick, emotional judgment.
Think of seeing a product priced at 9.99 instead of 10.00. Even though the difference is tiny, 9.99 feels noticeably cheaper because the leading number is lower.
In marketing this bias shapes how prices are set across products, sales, and promotions. Small changes at the end of a price can create a big shift in perception.
Charm Pricing Guide
Charm Pricing Research
In 2013, Gumroad analyzed all products on its platform priced under $6. They compared items with charm prices (ending in .99) to items with round prices (like $2 or $5).
Products with charm pricing converted at 3.5%, while round-priced products converted at 2.3%. This is a ~52% higher conversion rate for prices ending in .99!
The products were otherwise similar, so the main difference was the price ending. The result shows that even a small price change that does not affect real value can strongly change how people decide to buy.
In a real retail catalog experiment, the exact same dress was sold at three prices:
Even though $34 was cheaper, the dress priced at $39 sold the most. The $44 version sold less, as expected, but the key result is that $39 outsold the cheaper $34 option.
This shows that people do not always choose the lowest price. Prices ending in 9 can increase perceived value and attractiveness, likely because buyers focus on the left digit and interpret $39 as a better deal or higher-quality option than $34.
Charm Pricing Examples

1. Amazon
Amazon uses .99 pricing on millions of products. Shoppers scan fast and anchor on the first digit (19, not 20). The product feels meaningfully cheaper, even though the difference is 1 cent.

Starbucks often uses prices like $4.95 instead of $5.00. The left digit (4 instead of 5) triggers the left-digit effect, so the drink feels meaningfully cheaper. At the same time, .95 feels more premium than .99, which fits Starbucks’ “affordable luxury” positioning.
Features to Benefits Details
Features to Benefits means people care less about what a product has and more about what it does for them. A feature is technical, a benefit is how that feature improves someone’s life.
Think of a blender advertised as having “1200 watts.” Most people don’t know what that means. But say “blends smoothies in 10 seconds,” and suddenly it clicks.
In marketing this shift shapes product pages, ads, emails, and demos. Explaining benefits helps people imagine the outcome, not the mechanics, which makes decisions much easier.
Features to Benefits Guide
Features to Benefits Research

Old launcher

D - Free town
EA ran a controlled A/B experiment inside The Sims 3 game launcher to understand whether feature-oriented messaging or benefit-oriented messaging would drive more players to register their game.
The control (old launcher) was the standard launcher screen that showed many competing messages, generic registration benefits, and unclear reasons to sign up. Registrations from this control were low.
EA then tested 6 new variants, each representing a different style of messaging:
Every tested variant outperformed the old launcher, with lifts of +43% or more.
But the biggest finding was the gap between features and benefits:
All feature-style variants (A1, A2, B) performed worse than any specific-benefit variant.
Features to Benefits Examples

1. Apple
Feature: 5GB of storage.
Benefit: 1,000 songs in your pocket.
Apple didn’t sell storage. They sold a lifestyle upgrade in one sentence.

Feature: Organized channels, file sharing, app integrations.
Benefits: Slack users experience 48,6% fewer emails since they started using the platform.
Slack sells relief from overwhelm, not software tools.
Bandwagon Effect Details
Bandwagon Effect means we’re more likely to choose something when we see many others choosing it. Popularity acts like proof.
Think of hearing that everyone is watching a new show. Even if you weren’t interested before, you feel a pull to check it out, partly to fit in, partly to not feel left out.
In marketing this bias powers social proof, bestseller tags, reviews, waitlists, and visible community numbers. When people see a crowd, they assume the choice is safe and worth joining.
Bandwagon Effect Guide
Bandwagon EffectResearch
The study examined the bandwagon effect in luxury buying. It focused on how much people want a luxury product when they believe popular or high-status people already use it.
The researcher ran 3 experiments with 60 teenagers, 76 female students, and 73 male students/graduates.
When people saw a message saying “popular people use this product,” several things changed:
The study clearly showed that the bandwagon effect works: when a product is linked to an admired group, people want it more, pay more, and choose options that signal status.
Cialdini’s famous hotel-towel study showed that people follow the bandwagon effect.
Guests saw 3 messages:
Message #2 increased towel reuse by 26%, and the message #3 increased it by 33%, making it the most effective. The study proved that people follow what others do, especially when the group feels close or similar to them.
Bandwagon Effect Examples

1. Clubhouse
When Clubhouse launched, people rushed in not because they needed audio chats, but because thousands of others were already inside. The invite-only system made it feel like a growing party you didn’t want to miss. The Bandwagon Effect created explosive growth to 10M weekly users before the hype faded.

Game of Thrones became a cultural event partly because huge numbers of people were already talking about it - memes, spoilers, theories, and reactions filled the internet every week. Even people who normally don’t watch fantasy felt pressure to join in, just to understand conversations at work or avoid feeling left out. The Bandwagon Effect turned the show from a niche book adaptation into one of the biggest global TV phenomena, reaching over 19M viewers for the finale.

TBH grew insanely fast because its viral loop was engineered to spread inside one school at a time, not across a whole city or country. When the app launched in a new school, hundreds of students got the same notifications, polls, and compliments at once, creating the feeling that “everyone here is using it.”
This hyper-local explosion triggered a powerful Bandwagon Effect. Once a few classmates joined, the whole school rushed in, because no one wanted to be the only person not included.
TBH hit millions of downloads in weeks, not because the app was global, but because each school became its own viral ecosystem driven by social pressure and FOMO.
IKEA Effect Details
IKEA Effect means we value things more when we’ve put effort into making them, even if the final result isn’t perfect. Effort creates attachment.
Think of assembling a simple shelf at home. It might look a bit crooked, but because you built it yourself, it feels more special and harder to throw away than a similar one bought pre-assembled.
In marketing this bias shows up in customization tools, build-your-own kits, quizzes, and products that let people co-create the final outcome. When customers invest effort, their perceived value goes up.
IKEA Effect Guide
IKEA EffectResearch
One research found that even if participants had built a simple IKEA storage box by themselves, they were willing to pay 63% more for it, compared to a group of people who only saw the fully built.
IKEA Effect Examples

1. Nike By You
Nike’s Nike By You lets customers design their sneakers: colors, materials, engraving. People value these shoes far more than regular ones, even if the quality is identical. The effort of customizing makes the final product feel premium and emotionally important - pure IKEA Effect.

Notion doesn’t give you a rigid structure, you build your own system: pages, databases, templates. People overvalue their messy, homemade setups because they made them. The more time someone spends constructing it, the harder switching apps becomes (huge retention effect).
Contrast Principle Details
Contrast Principle means we judge things by comparing them to what came just before. The first item sets the frame, and everything after feels bigger, smaller, cheaper, or better based on that anchor.
Think of trying on a jacket after checking a much more expensive one. The new jacket suddenly feels like a bargain, even if the price hasn’t changed. The contrast makes it look better.
In marketing this principle shapes perception fast. Showing a premium option first makes standard options feel more affordable. Placing products side by side changes how each one is valued.
Contrast Principle Guide
Contrast Principle Research
Bone (1990) showed that contrast happens only when two options are very different. If the products are similar, people don’t separate them. They “pull” the new product toward the reference and rate it more similarly (assimilation).
The study found the effect depends on how alike the items are, how well people remember the reference, and how many related features come to mind. For marketing: contrast works only when the difference is obvious and big; if things look too similar, the contrast effect disappears.
A study showed that when people judge a product right after seeing something very good or very bad, their opinion shifts in the opposite direction. The extreme example changes how they imagine the product or how they read the rating scale. In short, a product can feel better or worse just because of what came before it.
Contrast Principle Examples

1. HelloFresh
HelloFresh ads always show the contrast between messy grocery lists, crowded stores, random ingredients vs their neat box with pre-cut portions and a simple step-by-step recipe card.
Dollar Shave Club’s iconic ad hits you with a direct contrast of traditional razor brands that charge bloated prices for unnecessary bells and whistles, while DSC costs only a few bucks a month.
By placing the expensive, over-engineered razors next to their simple cheap ones
Decoy Effect Details
Decoy Effect means adding a third, less appealing option can push people toward the choice you want. The weaker option makes the target option look like the smartest deal.
Think of choosing between two subscription plans. When a third plan appears that’s overpriced and poorly balanced, it suddenly makes the mid-tier plan look perfect. The decoy steers the decision without saying a word.
In marketing this effect shapes pricing tables, bundles, and memberships. A well-placed decoy guides customers toward the option with the best margin or value.
Decoy Effect Guide
Decoy Effect Research
A study of an online diamond retailer found that after introducing a “decoy” option, the retailer’s gross profit rose by 21.4 % across different diamond price segments.
The study tested whether adding a decoy option makes people pick more expensive hotel and restaurant offers. Researchers ran a pilot test and a few studies with 463 adults in the USA.
1. study (fast-food menu)Options:
Results:
2. Study Hotels (cancellation policies)Options:
Results:
The famous decoy-pricing example used 3 real subscription prices from The Economist:
In Ariely’s experiment, when all 3 options were shown, 84% of people chose the combo and 16% chose web-only, while 0% picked the pointless print-only option, making it a perfect decoy.
But when the decoy (print-only) was removed, 68% picked the cheaper web-only and only 32% chose the combo.
This shows how one “useless” option can massively shift preference toward a higher-priced product, simply by changing the comparison frame.
Decoy Effect Examples

1. Jamba Juice
Jamba introduced a slightly smaller-than-large cup priced almost the same as the big one. The medium suddenly looked bad, so customers jumped to the large. The decoy wasn’t meant to sell, its job was to push people up a size.

Panera tested 3 sizes: small, medium, and a barely-bigger-than-medium large. The medium served as the decoy. It made the largest soup look like way better value for only a tiny price jump.
Centre-Stage Effect Details
Centre-Stage Effect means we naturally prefer the option placed in the middle. Our eyes go there first, and our brain treats it as the safest, most balanced choice.
Think of picking a snack from a shelf or choosing a seat. The middle spot feels more comfortable and more “right,” even when all options are the same. The position alone pulls you in.
In marketing this effect shapes how people choose plans, products, and bundles. Putting the preferred option in the center increases its chances of being picked because it feels like the default.
Centre-Stage Effect Guide
Centre-Stage Effect Research
In this study, people had to choose from options that were literally identical (identical products on store shelves). Even with no differences at all, the middle positions dominated:
Christenfeld also found similar patterns in everyday behaviour, like people using toilet paper from middle dispensers more often than from the ends.
Across several experiments, people strongly preferred the middle option when choosing between similar items.
Centre-Stage Effect Examples

1. Netflix
When Netflix shows recommended titles in a row, the platform often places its top push (the show they want you to watch) dead center.

On category pages, Sephora frequently positions high-margin or trending products in the middle column of the 3-column product grid.