The Iyengar Jam Study: What Happened at a California Grocery Store
In the year 2000, two researchers walked into a supermarket in Menlo Park, California, and set up a table of jam. That sentence does not sound like the beginning of one of the most cited studies in modern psychology. It sounds like the beginning of nothing. A tasting booth. Free samples on a Saturday.
But what Sheena Iyengar and Mark Lepper did at that table would go on to reshape how psychologists think about freedom, how economists think about markets, and how product designers think about the apps on your phone.
The paradox of choice is this: more options do not lead to better decisions. They lead to fewer decisions, worse decisions, or no decisions at all. On some days, the researchers set out 24 varieties of jam. On other days, they set out just 6.
The table with 24 jams attracted more people. Abundance is magnetic. But of the shoppers who stopped at the table with 24 options, only 3% bought a jar. Of the shoppers who stopped at the table with 6 options, 30% bought one.
Ten times more people made a decision when they had fewer options to decide between. Psychologist Barry Schwartz would later call this the paradox of choice in his 2004 book of the same name. And in the space between browsing and choosing, something corrosive happens. People become less satisfied with whatever they eventually pick, because they can always imagine the option they did not.
If you have ever spent twenty minutes scrolling through a streaming platform only to watch nothing, you have already lived it.
What Is Decision Fatigue? The Science Behind Choice Overload
The jam study is elegant because it is simple. But the mechanism underneath it is not. What is actually happening inside your brain when you face 24 jars of jam, or 400 shows on a streaming platform, or 47 unread newsletters in your inbox?
The answer involves a concept called decision fatigue, and it is more physiological than you might expect.
In 2011, a research team led by Shai Danziger published a study that sent shockwaves through the legal community. They analyzed over 1,100 judicial decisions made by Israeli parole boards and discovered something troubling. Judges granted parole at a rate of roughly 65% after a meal break. By the time the next break approached, that rate had dropped to nearly zero. Not because the cases got worse. Because the judges got tired.
The brain’s capacity for deliberate decision-making is not infinite. It is a resource. Like a muscle, it fatigues with use. Roy Baumeister, the psychologist who coined the term “decision fatigue,” demonstrated this across dozens of experiments. After making a series of choices, even trivial ones like picking between colors of socks, people performed worse on subsequent tasks requiring self-control and judgment.
This is the hidden machinery behind Iyengar’s jam table. When you face 24 jams, your brain does not simply evaluate 24 flavors. It runs a comparison engine. It weighs one against another against another. And by the time it has processed even a fraction of the options, the cognitive budget for making a confident decision has been spent.
The result is not confusion, exactly. It is something worse. It is a low-grade paralysis disguised as browsing.
“More options do not lead to better decisions. They lead to fewer decisions, worse decisions, or no decisions at all.”
How Your Phone Became a 24-Jam Table That Never Closes
Iyengar published her jam study in the year 2000. The iPhone launched in 2007. Instagram in 2010. TikTok in 2016. Between then and now, the number of choices the average person faces per day has multiplied by an order of magnitude that no one has reliably measured, because we stopped being able to count.
Consider what happens in the first ten minutes of a typical morning. Before your feet touch the floor, you have been presented with email subject lines competing for your attention. News headlines ranked by algorithmic urgency. Social media notifications sorted by their ability to trigger a reaction. Group chat messages. App update badges. Calendar reminders.
None of these are individually overwhelming. But collectively, they represent dozens of micro-decisions, each one drawing from the same cognitive well that Baumeister’s research tells us is finite. By the time you have finished breakfast, you have already made more deliberate choices than a medieval farmer made in a week.
This is not a polemic against technology. The villain is the assumption, baked into nearly every digital product you use, that more is better. More content. More features. More options. More notifications.
The jam study proved, a quarter century ago, that more is often worse. The technology industry heard the finding and did the exact opposite.
Why Too Many Options Make You Miserable (The FOMO Effect)
There is a second layer to Iyengar’s paradox that rarely gets discussed.
When people in the jam study faced 24 options and managed to choose one, they reported lower satisfaction with their choice than the people who chose from 6. Schwartz explained this with a concept he called the “opportunity cost” of choice. When you pick one from six, you give up five. When you pick one from twenty-four, you give up twenty-three. The weight of what you did not choose scales with the number of options you rejected.
This is the engine that powers FOMO. It is not a character flaw. It is a predictable psychological response to environments designed to present more options than your brain evolved to process.
Your ancestors on the savanna did not face 24 varieties of anything. The human brain is a spectacular decision-making organ, but it was built for a world of limited options and immediate consequences. Move it into an environment of infinite options and abstract consequences, and it does not upgrade. It stalls.
Hick’s Law, described by British psychologist William Edmund Hick in 1952, formalizes this. The time it takes to make a decision increases logarithmically with the number of options. But more importantly, you increase the cognitive residue: that lingering sense of “did I pick the right one?” that follows you long after the decision has been made.
The Information Buffet: When Everything Is Good Enough
Here is where this stops being about jam and starts being about your daily relationship with information.
Each piece of content you encounter is a jar of jam. Each one asks you to evaluate, compare, and decide.
The cruel irony is that most of this content is not bad. Some of it is excellent. But excellence does not solve the paradox. It makes it worse. When everything is good enough to deserve your attention, nothing gets your full attention. You skim. You half-read. You open seventeen tabs and finish two.
Schwartz drew a distinction between what he called “maximizers” and “satisficers.” Maximizers need to explore every option before committing. Satisficers choose the first option that meets their criteria. His research found that maximizers, despite objectively making better choices, were consistently less happy with those choices.
The internet turned most of us into maximizers. We browse for the best article, the best podcast, the best use of our two free hours. And by the time we have finished browsing, the two hours are gone.
What If the Answer Is Not Fewer Options, But No Options at All?
This is the question that kept me up at night before I built One Good Thing.
Most apps that try to solve the problem of digital overload do so by giving you tools to manage the overload. Screen time trackers. App blockers. Do-not-disturb schedules. Notification managers. Focus modes.
These are all, at their core, more decisions. They are meta-decisions about how to manage your decisions. And they suffer from the same fatigue they are trying to cure.
What if, instead of helping you choose better, something simply removed the choice entirely? Not through restriction. Not by locking you out of your phone or guilt-tripping you about screen time. But by offering you exactly one thing, making it genuinely worth your time, and then stepping aside.
That is what One Good Thing does. You open the app. There is one card. Not a feed of cards. Not a recommended selection. One card. Today’s card. A headline. A body. Sometimes a conversation starter at the bottom.
You read it. You decide to Carry it or Let it Go. Then you close the app.
There is no second card to evaluate against the first. No “more like this” button. No algorithmic recommendation pulling you deeper. The paradox of choice cannot operate in an environment where there is no choice to be paralyzed by. One card removes the comparison engine entirely.
This is not minimalism as an aesthetic. It is minimalism as a cognitive strategy. The app was designed, from its first line of code, around the principle that Iyengar proved in a California supermarket twenty-six years ago: fewer options lead to more action, more commitment, and more satisfaction. If you want to understand the design philosophy behind that decision, I wrote about it in the founder story.
What Neuroscience Says About One Good Thing at a Time
There is a growing body of research suggesting that depth of engagement with a single piece of information is more valuable than breadth of exposure to many.
Neuroscientists at Princeton, in a study led by Uri Hasson, found that when a listener is deeply engaged with a narrative, their brain activity begins to mirror the speaker’s in a phenomenon called neural coupling. The more focused the attention, the stronger the coupling. The stronger the coupling, the deeper the retention.
Shallow engagement, the kind that characterizes scrolling, produces almost no neural coupling at all.
This is the neuroscience of why a single well-crafted thought can stay with you all day, while an hour of scrolling leaves you with nothing. Your brain does not retain what it skims. It retains what it sits with.
One Good Thing is built around that finding. The cards are short not because attention spans are short, but because a short, dense, surprising idea creates the optimal conditions for deep processing. Under two minutes. Not because that is all you can handle. But because that is all it takes, when the distractions are absent enough, for something to actually land.
“Your brain does not retain what it skims. It retains what it sits with.”
The Hidden Cost of Too Many Choices
Iyengar’s jam study is, at its deepest level, a study about freedom.
We assume that freedom means options. That the free person is the one with the most choices. That a free market is one with the most products on the shelf. That a free internet is one with the most content at your fingertips.
But the data tells a different story. The person facing 24 jams was, by every conventional measure, freer than the person facing 6. More variety. More opportunity. More room to express preference.
And that person was ten times less likely to act.
Freedom without constraint is not liberating. It is paralyzing. The hidden cost of too many options is not that you choose badly. It is that you stop choosing at all. You scroll instead of reading. You browse instead of watching. You save for later instead of engaging now. You accumulate options as a substitute for using them.
The most free you will feel on your phone tomorrow morning is not when you open an app with infinite content. It is when you open something that asks nothing of you except two minutes of genuine attention, gives you one idea worth carrying, and then tells you to close it and go live your day.
That is what One Good Thing was designed to be.
One card. One thought. Under two minutes. No feed. No scroll. No choice overload.
Free for 7 days. Then €1.99 a month, or €39.99 once, forever.
Frequently Asked Questions
What is the paradox of choice in psychology?
The paradox of choice is the finding that having more options to choose from often leads to worse decisions, more anxiety, and less satisfaction with the outcome. It was popularized by psychologist Barry Schwartz and is grounded in the Iyengar and Lepper jam study of 2000, which showed that consumers were ten times more likely to purchase when offered 6 options rather than 24.
What is the jam experiment?
The jam experiment, conducted by Sheena Iyengar and Mark Lepper in 2000, tested whether more product options led to more purchases. At a grocery store sampling booth, a display of 24 jams attracted more browsers but resulted in a 3% purchase rate. A display of 6 jams attracted fewer browsers but converted at 30%. The study is one of the foundational pieces of evidence for choice overload.
Does having more choices make you happier?
Research consistently suggests that beyond a certain point, more choices decrease happiness and satisfaction. Barry Schwartz’s research found that “maximizers” who exhaustively evaluate all options tend to make objectively better choices but report lower satisfaction than “satisficers” who choose the first good-enough option.
How do you overcome choice overload?
Strategies include reducing the number of options you consider, setting clear criteria before browsing, accepting “good enough” over “the best,” and using products designed around constraint rather than abundance. One Good Thing takes this principle to its logical conclusion by presenting one curated thought per day with no alternatives to compare against.
What is decision fatigue?
Decision fatigue is the deterioration of decision quality after a long session of making choices. Research by Roy Baumeister and others has shown that willpower and judgment draw from a limited cognitive resource that depletes with use. The Danziger parole study demonstrated that even trained judges make measurably worse decisions when their cognitive resources are depleted.
One Good Thing is available for iPhone at onegoodthing.space.
Free for 7 days. Then €1.99 a month, or €39.99 once, forever.
Questions? Get in touch.
Supratim Dam
Marketer turned iOS developer. Built One Good Thing alone in two months from Madrid, using Claude Code and an obsessive amount of research. Previously founded and sold a creative media agency.