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".
Life Event Effect Details
Life Event Effect means that people are more likely to switch habits and brands when they have undergone a life event. Changes like moving, having a child, starting a new job, or a breakup make old habits break.
Think of someone who just moved to a new city. They suddenly choose new brands, new routines, and new services , not because the products changed, but because their life context did.
In marketing this bias explains why timing matters so much. Brands that show up during life changes get a rare chance to form new habits.
Life Event Effect Guide
Life Event Effect Research
About 34% of US soldiers used heroin while fighting in Vietnam, and around 20% showed signs of addiction. After a major life change (coming back home) this behavior dropped fast.
In the first year after returning to the US, only about 1% became addicted again, even though 10% tried the drug again after returning.
This shows that when life context changes, behavior can change suddenly, even without treatment.
During research, researchers ran a survey among 2,370 people. They asked two things:
Overall, 21% of people who had a recent life event had switched brands, vs 8% of regular consumers (≈2.6X higher). And in 3 categories, life-event consumers were more than 3X more likely to have switched brands.
People whose age ends in “9” (eg, 29, 39, 49) are more likely to question the meaningfulness of their lives than people at other ages.
In their study, researchers examined the ages of first-time marathon runners and found that 9-enders were overrepresented by ~48% among participants aged 25-64.
Nine-enders were also more represented on an extramarital affairs site (men with ages ending in 9 were ~18% overrepresented).
This explains the whole idea of a midlife crisis.
Life Event Effect Examples
1. Starting new job - LinkedIn Premium, Notion, Slack
A new job resets tools, routines, and identity. LinkedIn usage spikes when people start searching for a new job. LinkedIn Premium converts best when users change job titles. Notion and Slack get adopted because teams rebuild workflows from zero.
When people move, they switch internet, furniture, and home services. Comcast and AT&T aggressively target people right after an address change. IKEA wins because moving breaks old habits, and people are open to new brands.
Underdog Effect Details
Underdog Effect means we root for people or brands that seem disadvantaged but still fight hard. It’s about telling a story of a small start, low budget, a big competitor to fight, and steady effort against tough odds. Effort against the odds makes us feel emotionally connected.
Think of a tiny startup showing how they build everything with almost no money while going up against a huge company. Their honesty and effort make you want them to win.
In marketing this bias shapes storytelling, brand positioning, and challenger messaging. When customers see a brand as the scrappy fighter, they support it more actively.
Underdog Effect Guide
Underdog Effect Research
The researchers found that the Underdog Effect makes people more likely to buy, choose, and stay loyal to a brand.
This effect is even stronger for people who see themselves as underdogs, especially when they are buying something for themselves, not for others. It also works better in countries where underdog stories are an important part of the culture.
Underdog Effect Examples
1. Apple's "1984" commercial
In its early days, Apple positioned itself as the underdog against the giant IBM. Their now iconic "1984" commercial, showed a dystopian future dominated by "Big Brother" (IBM), with Apple as the rebellious force breaking the mold. This ad solidified Apple's reputation as the innovative and rebellious alternative to the status quo.
Avis, the car rental company, was always in the shadow of Hertz, who was an industry #1. Avis used this situation to their advantage with their "We Try Harder" campaign. Because they were #2 in the market, they had to put in extra effort to please their customers. This campaign was immensely successful and helped Avis increase its market share.
When a newly-created Instagram account of an egg announced that it wanted to beat Kylie Jenner in terms of the most-liked photo, people responded. A simple egg photo collected over 52M likes within days.
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.
Authenticity Effect Details
Authenticity Effect means we trust and value things that feel real, honest, and unpolished. When something looks too staged or too perfect, our guard goes up.
Think of a founder recording a simple phone video explaining why they started their company. No studio, no script, just a real person talking. It feels more believable than a glossy ad saying the same message.
In marketing this bias shapes brand voice, storytelling, behind-the-scenes content, and honest communication. When people sense genuineness, their trust and loyalty rise fast.
Authenticity Effect Guide
Authenticity Effect Research
The study examined how the value of a sponsored message and the credibility of an influencer shape trust, and how that trust then drives brand awareness and purchase intention.
Researchers surveyed social-media users who follow influencers.
Overall, influencer marketing works best when the content is genuinely helpful and the influencer is seen as credible, because these two factors build trust that leads people toward the brand and toward buying.
Authenticity Effect Examples
1. Liquid Death
Liquid Death sells canned water but uses metal music energy, dark humor, and anti-corporate vibes. Because the tone feels real and not “safe marketing,” people believe the brand more and share it more. Authenticity turned a commodity product (water) into a cult brand worth over $1B.
Nerdy Nuts is a small Peanut Butter, family business that has grown crazy fast due to the quirky product and witty marketing that feels authentic. Customers see the real founders, real kitchen energy, and honest communication, which makes the brand feel trustworthy and human.
This authenticity, combined with weekly product drops and creator partnerships, helped Nerdy Nuts grow from $7k to over $1M in sales within 4 months.
Nostalgia Effect Details
Nostalgia Effect means we respond more strongly to things that remind us of the past. Memories, old styles, and familiar moments create warm feelings that lift our judgment.
Think of hearing a song from your childhood and instantly feeling more positive, even if your day was stressful. The memory colors the moment.
In marketing this bias shapes retro packaging, old-school branding, classic sounds, and “remember when” campaigns. Nostalgia makes products feel safer, warmer, and more meaningful.
Basically, the past makes the present feel better.
Nostalgia Effect Guide
Nostalgia Effect Research
This research ran 6 experiments. In every experiment, nostalgia made people value money less or want money less.
Key findings:
Nostalgia increases social connectedness (people feel closer to others). When this social need is filled, people feel safer and less focused on self-protection or financial security. Because of that, money becomes less important, so they are more willing to spend or give.
When nostalgia is activated (ads, memories, old products, retro style), people spend more easily because they feel emotionally full and less attached to their money.
Nostalgia Effect Examples
1. Pokémon GO
Pokémon GO exploded in 2016 because it brought back childhood memories of collecting creatures. Millions of adults who hadn’t played games in years returned because the app made them feel like kids again. Nostalgia powered record downloads, global crowds, and $500M revenue in the first 60 days.
Stranger Things became a global hit because it recreated the exact look and feel of 1980s movies: neon colors, synth music, walkie-talkies, arcade games, and Spielberg-style adventure.
Adults who grew up in the 80s and 90s felt a strong emotional pull. The show reminded them of childhood summers, old friendships, and classic films. This nostalgia made people binge the series, share it like crazy, and turned a mid-budget show into one of Netflix’s biggest cultural phenomena.
Humor Effect Details
Humor Effect means we remember things better when they make us laugh. A joke, a funny twist, or a light tone sticks in the mind far longer than something serious and flat.
Stories & humor are the ultimate shortcuts to deeper connections and earning trust of your customers. Humor bypasses skepticism.
Think of seeing a billboard with a clever joke. Even if you glance at it for a second, the line stays with you, while dozens of normal ads disappear instantly.
In marketing this bias shapes brand voices, ads, emails, and social posts. Humor boosts attention, recall, and shareability because it gives the brain a little reward for paying attention.
Humor Effect Guide
Humor Effect Research
This meta-research from 1992 reviews dozens of studies on how humor works in advertising.
Humor grabs attention very well but does not always convince people. About 24% of TV ads used humor, and 94% of advertisers said humor is an effective way to get attention, while 55% of research directors said humor works better than non-humor ads for attention.
Humor consistently lifts attention, but its effect on understanding the message is mixed, with:
Humor also does not guarantee stronger persuasion, although one analysis from 1982 found that 31% of humorous ads performed above average in persuasion tests.
The strongest finding in the entire review comes from the role of liking. A large 1991 study with almost 15,000 interviews showed that liking a commercial predicted which ad would win in sales 87% of the time, and a simple like-or-not-like measure predicted success 93% of the time.
People who liked a commercial a lot were also twice as likely to be persuaded. Humor supports this effect because when people felt an ad was funny or clever, it predicted success 53% of the time, while calling an ad boring predicted failure 73% of the time.
Overall, humor is great for getting attention and increasing liking, and since liking is one of the strongest predictors of sales, humor can indirectly make ads more effective, especially when the humor is connected to the product and used for simple, low-involvement decisions.
Humor Effect Examples
Their first ad used deadpan humor, swearing, and absurd scenes to explain a boring product: razor subscriptions. The humor made the message unforgettable, “Our blades are f***ing great.”.
Result: over 12k orders in 48 hours and a company later sold for $1B.
After the 2008 shoe-throwing incident became global meme material, Alex Tew created a funny browser game called Sock and Awe in just 3 hours.
The humor made it instantly shareable. By day 3, it had been played 1.4M times, and by day 6, the site reached 9M visitors.
The game was sold within days, and the team later used the traffic to collect 120k emails, helping them launch their next project (PopJam).
Old Spice used surreal, rapid-fire humor that completely broke deodorant-ad conventions. The absurd style made the brand memorable to both men and women, turning a dying product line into a cultural hit. Sales jumped 125% year-over-year after the campaign.
Curiosity Gap Details
Curiosity Gap means we feel a strong pull to fill in missing information. When we see a hint without the full answer, our brain wants to close the gap.
Think of reading a headline that teases a surprising fact but doesn’t give the full story. You click because the missing piece bothers you just enough to take action.
In marketing this gap drives engagement. Teasers, questions, partial reveals, and open loops make people lean in because they want to know what comes next.
Curiosity Gap Guide
Curiosity Gap Research
In a study from 2007, people chose between a sure thing (cash) and a mystery prize. When the researchers gave them just a little information about the mystery box (not the whole truth), curiosity shot up. People became more than twice as likely to choose the unknown prize instead of the cash. That small tease created a curiosity gap, and the urge to learn the missing info pushed them to take the risk.
A large analysis of 8,977 headline A/B tests found that headlines with an optimal “curiosity gap” achieved the highest CTR.
Upworthy’s data showed that only ~9% of very vague headlines gained clicks by adding info, whereas over 50% of overly detailed headlines actually saw ~5–10% fewer clicks.
This supports Loewenstein’s information-gap theory: headlines that leave readers guessing (not too little, not too much) can boost engagement.
Research on email marketing showed that using curiosity gap can lift open rates. In one study, 33% of recipients opened an email solely due to a compelling, curiosity-inducing subject line. Adding personalization further amplified this effect - personalized, curiosity-gap subject lines saw open rates climb by ~35%.
Curiosity Gap Examples
Ogilvy put a cheap eye-patch on a perfectly normal model wearing Hathaway shirts. This made people instantly curious about the model.
The first ad ran in The New Yorker in 1951. Within a week, every Hathaway shirt in New York was sold out.
In 2004, Heyah flooded cities with a strange red hand logo and a website called “nadchodzi.pl” (“it’s coming”) - but didn’t reveal the brand.
People kept asking “What is this? Who is behind it?” The curiosity gap exploded, driving 1.2M unique visitors before launch.
When the reveal finally came, Heyah got over 300k users within the first month.
Familiarity Bias Details
Familiarity Bias means we trust and prefer things we already know. Familiar options feel safer, easier, and less risky than new ones, even if the new ones might be better.
Think of choosing a brand you’ve bought for years instead of trying a new one with better reviews. The comfort of the known beats the potential of the unknown.
In marketing this bias rewards consistency. Repeated exposure, steady branding, and showing up often make your product feel familiar, and familiarity drives choice.
In other words, we pick what feels known, not always what’s best.
Familiarity Bias Guide
Familiarity Bias Research
The study tested how being familiar with a brand, having previous online-shopping experience, and the amount of product information shown on a website, influence how risky people think online shopping is and whether they intend to buy.
The results:
Familiar brands and previous online shopping experience significantly reduced perceived risk and increased purchase intention. However, surprisingly, the amount of product information provided (lots vs little) did not significantly affect perceived risk or purchase intention.
Familiarity Bias Examples
1. Trello
Trello exploded because it took the Kanban board, a format millions already knew from offices, factories, and whiteboards, and turned it into super simple drag-and-drop software.
GPT-3 was powerful, but almost nobody used it because the interface felt technical and abstract. When OpenAI released ChatGPT with a simple chat-style UI, something everyone already knew from Messenger/WhatsApp, usage exploded within days.
Among Us blew up because its core gameplay was basically the digital version of Mafia/Werewolf/Secret Hitler - games millions already knew from parties.
Curse Of Knowledge Details
Curse of Knowledge means once we know something well, we forget what it’s like not to know it. Explaining becomes harder because the basics feel too obvious to mention.
Think of an expert trying to teach a beginner and rushing through steps that seem simple to them but confusing to everyone else. The gap comes from knowing too much, not from explaining badly.
In marketing this curse makes messages unclear and overloaded. Teams assume customers understand terms, features, or steps that actually need simple language and clean guidance.
Curse Of Knowledge Guide
Curse Of Knowledge Research
In a classic study, people (tappers) tapped out well-known songs and expected listeners to understand them 50% of the time. In reality, listeners guessed only 2.5% of the songs correctly.
The tappers were shocked. They couldn’t not hear the song in their head, illustrating how knowledge “curses” us by making others’ ignorance unimaginable.
Researchers gave college graduates tasks on two websites:
Even high-literacy users finished tasks nearly 3 times faster on the plain-language site, and succeeded in 93% of tasks, versus many struggles on the wordy site.
In other words, simplifying text dramatically improved users’ speed and success. This backs up the idea that “dumbing down” content (really just using clear, everyday words) saves people time and effort without losing educated readers
Curse Of Knowledge Examples
1. Dropbox’s demo video
When Dropbox launched its cloud storage, the concept was foreign to most people. Instead of using technical terms, Dropbox created a 3-minute video showing how it works. No mention of protocols or data centers, just a relatable scenario.
In 2001, the iPod wasn’t advertised as a “5GB portable MP3 player with 1.8-inch HDD.” It was sold as “1,000 songs in your pocket.”