The 8 Core Drives of Gamification #7: Unpredictability & Curiosity

Why do people pour billions of dollars into slot machines every year, knowing the odds are stacked against them? Why does opening a mystery box feel more exciting than buying the exact item you wanted?

The answer is Core Drive 7: Unpredictability & Curiosity — one of the most powerful (and dangerous) forces in the Octalysis Framework. The pull of unpredictability and curiosity is the reason gambling exists, the reason loot boxes generate billions, and the reason you can’t stop checking your phone for notifications.

This analysis is adapted from Actionable Gamification: Beyond Points, Badges, and Leaderboards — the definitive guide referenced by 3,700+ academic publications.

Table of Contents

About the Creator of the Octalysis Framework

Yu-kai Chou created the Octalysis Framework after studying gamification since 2003 — years before the term entered mainstream vocabulary. As a Human-Systems Architect & Behavioral Designer, his framework has been applied by LEGO, Microsoft, Porsche, Coca-Cola, Salesforce, and MrBeast, impacting over 1.5 Billion Users.

Chou has taught the Octalysis methodology at Harvard, Stanford, Yale, Tesla, Google, BCG, and IDEO.

His work has been cited by Harvard, Stanford, MIT, Forbes, Wall Street Journal, Wired, US Department of Energy, NIST, NSF, NCBI, US Department of Education, ClinicalTrials.gov, and 3,700+ more academic publications. Explore his books here.

Core Drive 7: Unpredictability & Curiosity

Unpredictability & Curiosity is the seventh Core Drive in the Octalysis Gamification Framework and is the main force behind our infatuation with experiences that are uncertain and involve chance.

As mentioned in earlier chapters, our intellectual consciousness is inherently lazy, and if tasks at hand do not demand immediate attention, the neocortex delegates the mental legwork to our subconscious mind, or “System 1” according to Economics Nobel Prize winner and psychologist Daniel Kahneman.

The intellectual consciousness only wants to be disturbed when it is absolutely necessary, such as when a threat is present or when the brain encounters new information it hasn’t processed before.

Indeed, Oren Klaff, author of Pitch Anything, states that during meetings, people pay attention to what you say until they can fit you into a pattern that they have previously recognized. Once they fit you into a recognized pattern, they immediately zone out.

Therefore, it is important to give a pitch that continuously serves unexpected and unpredictable information to keep people engaged.

Coupled with this is our natural curiosity to explore. Exploring the unknown, though dangerous, helped our ancestors adapt to changing environments and discover new resources to survive and thrive.

Jesse Schell, game designer and author of Art of Game Design: A book of lenses, even goes as far as defining the word “fun” as “pleasure with surprises.” Why is the “surprise” element so important in *fun*?

In this chapter, we will explore how this Core Drive of Unpredictability & Curiosity drives our behavior and how a system designer can effectively design this into their experiences.

Gambling and Variable Rewards

If I told you to play a game, where you continuously press a button and every ten times you press it, you give me $5, would you play it?

The rational reader would not only turn down this offer but would feel utterly insulted that I tried to dupe you into playing in the first place.

Now what if the terms change, and I told you that out of a hundred people, two people who play this game will win $10 back?

You may ponder this a little bit, but still reject it. The offer is not as insulting as before though, just not economically attractive.

But what if I told you that every time you press the button, you may periodically win some money back, and there is an extremely small but possible chance of winning $10,000?

I can’t exactly predict what my smart rational readers would do in this case, but I do know that every single day millions of people throughout the world play the game I mentioned above. Most commonly known as slot machine gambling, players are consistently losing money every time they pull a lever or press a button, but are engaged, even addicted, to the unpredictable chance of winning a lot of money back. With the *right* risk/reward incentive, the game suddenly becomes so much fun!

Studies have shown that we are more engaged in an experience when there is the possibility of winning than when we know our odds for certain.  If we *know* we will receive a reward, our excitement only reflects the emotional value of the reward itself. However, when we only have a chance to gain the reward our brains are more engaged by the thrill of whether we will win or not.

Gamification and the Skinner Box

There’s a substantial amount of research on how the unknown and the unpredictable intrigues and engages our minds. One of the most famous motivational design case studies that explored this phenomenon is the Skinner Box

The Skinner Box was an experiment conducted by the scientist B. F. Skinner, who placed rodents and pigeons in a box with a lever in it. In the first phase, whenever the animal presses the lever(the *Desired Action*), food came out. As long as the animal continuously pressed the lever, food would continue to be dispensed.

The end result is that when the animal was no longer hungry, it would stop pressing the lever. This makes a lot of sense – the animal is no longer hungry and does not need food anymore.

The second phase, however, introduced unpredictability into the test mechanics. When the animal pressed the lever, there was no guarantee that food would be dispensed as it did before. Sometimes food came out, sometimes nothing came out, and sometimes even two pieces of food came out.

Skinner observed that with these mechanics in place, the animal would constantly press the lever, regardless of whether it was hungry or not.

The system was simply messing with its brain: “*Will it come out? Will it come out? Will it come out?*”

Here we see that satisfying our burning curiosity is intrinsically motivating to our primitive brain, sometimes more so than the extrinsic reward of food. Have you ever seen a person so addicted to gambling that he forgot that he was tired, hungry, or even thirsty?

I often hear critiques of how the Points, Badges, and Leaderboards in gamification simply turns the world into a large Skinner Box, where people are manipulated to mindlessly doing meaningless tasks. I feel the more profound lesson from the Skinner Box is not that Points and Badges motivate people, but that unpredictable results stemming from Core Drive 7 can drive obsessive behavior. 

Glowing Choice (Game Technique #28)

Within Core Drive 7: Unpredictability & Curiosity, the game element “Glowing Choice” (#28) is an often used example of how to lead players in the right direction by appealing to their curiosity (this is especially used in the Onboarding Phase).

Most players don’t enjoy reading a huge manual or watching a long video before beginning a game; players would rather have the option to jump right in and test things out- this is where the Glowing Choice comes into play. In many role-playing games, when a player is uncertain what the next Desired Action is, a specific computer character might be highlighted with a glowing exclamation point that prompts the player to engage with him/her.

Once engaged, the character will reveal the following quest or the next clue to help the player move forward in the game.

The player now knows the next Desired Action.

Contrasted with the Desert Oasis game technique mentioned in the Core Drive 2 chapter where the designer highlights a Desired Action by clearing out everything surrounding it, the Glowing Choice technique is about making the Desired Action shine like a bright star in the midst of a complex environment.

You can apply this method with apps by placing a strong emphasis on a key feature that represents the Desired Action that users need to be guided towards. Many apps do this by having a question mark on top of the key feature, or an arrow that points directly to what they want their potential customers to focus on.

I always tell my clients, “Never allow your users to accidentally stumble upon a bad experience.” If users cannot figure out what to do within 4 seconds then they will become disengaged. If a user clicks on any button or tab and reaches a dead end, they are penalized for doing the Desired Action.

A great implementation of the Glowing Choice technique is seen in the game Candy Crush.

Like we discussed previously, if the app detects that you have not made a move within a few seconds, it will start to show you a possible action by having the option glow. Now any person who has spent some time on Candy Crush will know that following those actions will mostly likely lead you to failure, as they are almost never the optimal move. Some people wonder if these choices are there to purposely guide people into failure.

In reality, Candy Crush is not purposely trying to lead users to failure; they correctly recognize that having users move swiftly through the game even if this leads to a loss is far better than having them feel stuck and uncertain of what action to take.

When a player loses, she plays again. When a player is stuck, she may very well leave the app and go check her email. The Glowing Choice helps keep the game flowing.

The key to good design is that users don’t need to think about committing the Desired Actions. In fact, users should have to think hard and decide to not take the Desired Action if they don’t want to do it. If there was a huge animated pointing arrow that tells you to click on a certain button within an app, the user can still choose to not click it, but her brain has to work harder to avoid it.

Once your customer clicks on the question mark or the arrow, the question mark should disappear. The players can then click on the next highlighted feature to find out what it does and why it helps them.

There are many successful apps and games that implement the Glowing Choice game technique to guide users through the Onboarding experience and the discerning designer should examine how they implement it.

Mystery Boxes (Game Technique #72)

One of the most common ways to use Core Drive 7: Unpredictability & Curiosity is through reward structures. Instead of giving users Fixed-Actions Rewards where the steps to obtain them are well-understood- a strategy that focuses on Core Drive 4: Ownership & Possession through the “Earned Lunch” Game Technique- you can build unpredictability into the experience by altering the context of how the reward is given or the nature of the reward itself.

In games, there are “loot” or “drops,” which are random rewards that appear once the player achieves a win-state such as opening a treasure box or defeating an enemy. Oftentimes, this unpredictable process is what drives players in the Endgame Phase. I call this technique Mystery Boxes or Random Rewards.

With random rewards, the participant receives an unknown reward by completing a required action. Using this technique recreates the excitement that children have on Christmas Eve.

They see the gifts under the tree and know that they won’t find out what they are until Christmas morning. The anticipation of getting the gift, even though they have no idea what’s in the boxes, is part of what makes the experience so exciting.

One example of this technique can be found at holiday parties in the form of the White Elephant gift exchange. Also known as the “Gift Swap”, this game provides a mechanism for distributing inexpensive or undesirable gifts (often from previous holiday seasons) among participants.

The exchange starts with each participant providing a wrapped gift for the gift pool, and then drawing (unpredictability in itself) a number to determine the order in which they will select a gift. The first person selects and opens a gift from the pool. The next participant can then either select from the pool of unopened gifts or “steal” the opened gift from the first participant, who then has to reselect a replacement gift from the pool.

The next player has the option to select from the pool or “steal” either gift from the previous players. This goes on until the last player selects the last gift or steals from one of the others, which causes the individual whose gift is stolen to open the last gift. Again, in this case, everyone knows that once they complete the game, a reward will be earned, but what the reward is can only be known at the end.

A second example of Random Rewards is the blind box, the model that turned Pop Mart into a multibillion-dollar collectibles company. Customers pay a fixed price for a sealed box from a themed series, knowing they will get one figure but never which one. Every series also hides a rare “secret” figure, typically at odds around 1 in 72, so each unboxing carries a jolt of hope.

The formula itself is not new. Woot has shipped its famous “Bag of Crap” since the 2000s: a random assortment of goods sold to customers who happily pay for the privilege of not knowing what will arrive.

Pop Mart proved the same principle at global scale when its Labubu figures sold over 100 million units in 2025. People are not just buying a toy; they are buying the moment of finding out.

Each opening feels like unwrapping presents on your birthday. It keeps customers coming back for more.

Want to see which Core Drives your product is actually hitting, and where Core Drive 7 could multiply engagement? Run it through my free Octalysis Tool.

Easter Eggs (Game Technique #30)

Different to Mystery Boxes, Easter Eggs (or Sudden Rewards) are surprises that are given out without the user acknowledging it beforehand. In other words, where Mystery Boxes are unexpected rewards based on a certain expected trigger, Easter Eggs are rewards based on unexpected triggers.

Participants love the element of surprise and because these rewards are so unexpected, the added feelings of excitement and good luck make the experience enjoyable. Sudden rewards incentivize customers to keep coming back in the hopes that they can inadvertently feel the same excitement again.

Easter Eggs are effective in two ways: They get great word-of-mouth because everybody loves to share something exciting and unexpected that happened to them that day. They’ll tell their friends about what they got and their friends will want to participate in the hopes that they’ll get an Easter egg as well.

Easter Eggs also create speculation of what triggered it in the first place.

If the Easter Egg seemed to be random, participants will wonder how they can replicate the experience in order to “game” the system. They will start to develop theories about how they won, and they will commit the assumed Desired Actions over and over again to either prove or disprove these theories.

A good example of an Easter Egg is the “Chase Picks up the Tab” program. Once enrolled in the program, whenever a Chase customer swipes their Chase credit cards (the Desired Action), there is a very small chance the customer will get a text from Chase that says (paraphrased), “Chase just picked up the tab! Your $5 will be credited back to your account. Have a nice day.” Though the reward dollar amount is not great, it compels consumers to regularly swipe with their Chase cards instead of other cards because customers want to see if they can “win” again this time. Oftentimes, users will also tell their friends about their win, which may compel them to sign-up to this “game”.

Rolling Rewards (Game Techniques #74)

Another type of reward context that is fueled by Core Drive 7: Unpredictability & Curiosity is the Rolling Reward, or sometimes called the “Lottery”.

The key idea of rolling rewards is the rule that somebody has to win each period, and so as long as you “stay in the game” for long enough, the chances of you winning increases linearly.

In small settings, Rolling Reward designs are seen in forms such as “Employee of the Week” where employees work hard, hoping that one day they will be the one that earns that status and recognition (note: Mario Herger in his book, Enterprise Gamification, suggests that Employee-of-the-Week programs won’t work in countries and cultures that frown upon individual recognition).

Another form of Rolling Reward is when an employer or big client states, “After this project, one of you will get a free vacation to Maui for two weeks!” In fact, at most workplaces, the thought of being promoted one day is in itself a Rolling Reward – someone has to become the new Vice President: I hope it’s me.

On a larger scale Rolling Reward programs have low barriers to entry and the rewards are substantial (think state or national lotteries), but there’s a very slim chance to win, regardless of how long you spend playing the “game”.

Yes, individuals can increase their odds of winning by performing more of the Desired Action, such as purchasing additional tickets, or collecting additional entries but again, the larger the program, the more difficult the odds.

The reason why lotteries work so well is because our brains are notoriously bad at processing small percentages.

We can’t conceptually understand the difference between “one in ten million” and “on in a hundred million.” We just register both odds as “a very small chance” without really comprehending that you could be winning the “one in ten million” prize ten times before you can win the “one in a hundred million” prize!

Robert Williams, a professor who studies lotteries at the University of Lethbridge states, “we have nothing in our evolutionary history that prepares us or primes us, no intellectual architecture, to try and grasp the remoteness of those odds.”

And as a result, as long as there is some chance, people are willing to invest small amounts of money to obtain a gigantic reward.

Rolling rewards work on a number of levels. For starters, because they have moderately low barriers to entry, they can easily attract a large number of participants. Furthermore, if a participant actually wins, they may easily become a fan for life, simply because they feel that they were chosen to win.

Like described before, this is the “calling” part of Core Drive 1: Epic Meaning & Calling.

Core Drive 7: The Bigger Picture

Core Drive 7: Unpredictability & Curiosity is a powerful black hat core drive that is intrinsically thrilling. For any engagement design, it is productive to ask yourself, “Is there any way to add a little bit of randomness and chance to the process?” By using techniques that generate curiosity, companies can drive their customers to engage with their product and with techniques that design for unpredictability, companies can retain these customers for much longer into the Endgame Phase.

Working with White Hat Core Drives, Core Drive 7 is a great way to inspire Epic Meaning & Calling, complement Empowerment of Creativity & Feedback, and improve and increase the values of Ownership & Possession. Working with other Black Hat Core Drives, Unpredictability & Curiosity matched with Scarcity & Impatience, creates obsessive and addictive behaviors, while generating the negative emotions of fear and worry if properly matched with Core Drive 8: Loss & Avoidance.

Frequently Asked Questions

What is Unpredictability & Curiosity in gamification?

Unpredictability & Curiosity is Core Drive 7 in Yu-kai Chou’s Octalysis Framework. It represents the drive to find out what happens next when you don’t know. This is the primary driver behind gambling, mystery boxes, and variable rewards. It also drives curiosity — wanting to learn, explore, and discover new things.

What is the connection between Core Drive 7 and the Skinner Box?

B.F. Skinner’s experiments showed that variable reward schedules (unpredictable rewards) create stronger behavioral responses than fixed schedules. This is the psychological foundation of Core Drive 7. When users don’t know when or what reward they’ll receive, they stay engaged longer — which is why slot machines, loot boxes, and mystery rewards are so compelling.

What game techniques use Unpredictability & Curiosity?

Key game techniques include: Glowing Choice (Game Technique #28) that highlights intriguing options, Mystery Boxes (Game Technique #72) with unknown contents, Easter Eggs (Game Technique #30) that reward exploration, Rolling Rewards (Game Technique #74) that vary with each interaction, and Random Rewards that create variable reinforcement schedules.

Is Unpredictability & Curiosity a Black Hat core drive?

Yes, Unpredictability & Curiosity is a Black Hat, Right Brain core drive. It’s Black Hat because it creates addictive engagement patterns — users feel compelled to continue not out of empowerment but out of uncertainty. It’s Right Brain because it appeals to emotional and intrinsic responses rather than logical calculation. This combination makes it one of the most powerful but potentially harmful core drives if misused.

Explore All 8 Core Drives of the Octalysis Framework

The Octalysis Framework identifies 8 Core Drives that power all human motivation. Understanding how they work together is key to effective gamification design:

1. Core Drive 1: Epic Meaning & Calling — Being part of something greater than yourself
2. Core Drive 2: Development & Accomplishment — Making progress and achieving mastery
3. Core Drive 3: Empowerment of Creativity & Feedback — Expressing creativity and seeing results
4. Core Drive 4: Ownership & Possession — Owning things and wanting to improve them
5. Core Drive 5: Social Influence & Relatedness — Social elements that drive behavior
6. Core Drive 6: Scarcity & Impatience — Wanting something because you can’t have it
7. Core Drive 7: Unpredictability & Curiosity — The drive of not knowing what happens next (You are here)
8. Core Drive 8: Loss & Avoidance — Avoiding negative outcomes and loss

Related frameworks: White Hat vs Black Hat Gamification | Left Brain vs Right Brain Core Drives | The Strategy Dashboard

Explore Yu-kai’s Other Frameworks

The Octalysis Framework is just one of Yu-kai Chou’s systems for understanding human motivation. Explore how these principles extend to life design, economics, and society:

• 10,000 Hours of Play — Gamifying Real-Life Success
• Economy/Tokenomics Design Framework
• The Digital Convergence Model

Learn More in Actionable Gamification

This Core Drive is explored in depth in Actionable Gamification: Beyond Points, Badges, and Leaderboards — the definitive guide to designing engagement using the Octalysis Framework, referenced by over 3,700 academic publications. Get the book →

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