On 6 February 2026, the European Commission told TikTok that its design might be illegal. Not its content moderation, not its data handling, its design: infinite scroll, autoplay, push notifications, and a recommender system that keeps serving “just one more” video. The Commission’s preliminary finding under the Digital Services Act concluded that these features push users into what it called an autopilot state, and that TikTok had not properly assessed the harm. Five months later, in July 2026, the Commission charged Meta on similar grounds. Penalties under the DSA can reach 6% of global annual turnover.
Every one of those features traces back, directly or indirectly, to a single framework that product teams have used as a playbook for a decade: the hooked model. If you have ever shipped a streak counter, a variable reward, or a re-engagement notification, you have built with it, whether you named it or not. So it is worth understanding what the model actually claims, why it works, and where the ground under it has shifted so much that the same design that won you a growth award in 2021 can now open a regulatory file.
What the hooked model actually is
Nir Eyal published Hooked: How to Build Habit-Forming Products in 2014. The core idea is a four-step loop that, run enough times, moves a behavior from something a user decides to do into something a user does without deciding. The four steps:
Trigger. Something starts the loop. External triggers are the obvious ones: a notification, an email, an app icon with a red badge. Internal triggers are the ones that matter more, because they live in the user’s head. Boredom, loneliness, uncertainty, the itch to check something. Eyal’s argument is that a product becomes a habit when it attaches itself to an existing internal trigger, so the user reaches for it before a notification ever fires.
Action. The simplest possible behavior done in anticipation of a reward. Pull to refresh. Tap play. Open the app. Eyal leans on BJ Fogg’s behavior model here: a behavior happens when motivation, ability, and a trigger meet at the same moment. The design job is to strip friction until the action takes almost no effort.
Variable reward. This is the engine, and it is worth its own section below. The reward for the action is not fixed. Sometimes the feed is boring, sometimes it is fascinating. That unpredictability is what keeps people coming back.
Investment. The user puts something into the product that makes it better next time: data, content, followers, a tuned recommendation, a streak they do not want to break. Investment does two things. It loads the next trigger (you get notified when someone replies to the comment you invested in writing), and it raises the switching cost. A product you have poured effort into is harder to abandon.
Run the loop enough times and the behavior sticks. That is the whole claim.
Variable rewards do most of the work
If you strip the model down to one mechanism, it is the variable reward. Psychologist B.F. Skinner showed in the 1950s that a pigeon pressing a lever for food pellets pressed hardest and longest when the pellets arrived unpredictably, not on a fixed schedule. The same wiring runs in people. A reward you can predict is satisfying once. A reward you cannot predict is something you check again and again.
Duolingo is the cleanest modern example, partly because it is one of the few companies open about the mechanics. The product is built around a single daily behavior: complete one short lesson. Everything else, the characters, the leagues, the widgets, the notifications, exists to pull you back to that one rep. The streak counter is the investment layer, and it runs on loss aversion: the longer your streak, the more it hurts to lose, so the more you protect it.
The numbers are not small. Duolingo reported roughly 47.7 million daily active users and 10.9 million paid subscribers in 2025, with daily actives up 36% year over year. The company has publicly credited its streak and gamification systems with cutting churn from around 47% in 2020 to about 28% in its major markets. Whatever you think of the aesthetics, the loop works, and it works without heavy paid acquisition. That is the promise the hooked model makes, and for products like language learning where the habit genuinely serves the user, it delivers.
The chapter of Hooked almost nobody quotes
Here is the part product teams tend to skip. Eyal did not write a manual for capturing attention and leave it there. The book includes a chapter on ethics, and inside it a tool he calls the manipulation matrix. In an era when most of the industry only wanted to know how to raise retention, putting an ethics chapter in a design book was not the default move, and it is the part of the framework that has aged best.
The matrix asks two questions about whatever you are about to build:
- Does it materially improve the user’s life?
- Would the maker use it themselves?
The two answers give you four quadrants:
- Facilitator (yes and yes). You use it and it improves your life. Eyal’s target. Build here.
- Peddler (improves lives, but the maker would not use it). Good intentions, blind spots. You are probably missing something about the user you are building for.
- Entertainer (the maker uses it, but it does not materially improve anyone’s life). Fun, harmless, but you are relying on a fad, not a habit worth having.
- Dealer (neither). Eyal’s own word for this square is exploitation.
The matrix is not a rigorous ethical system and Eyal never claimed it was. But it does something useful: it forces the builder to sit in the user’s chair and ask whether the habit being engineered is one the user would thank you for. Most of the design that regulators are now investigating fails the first question badly. Infinite scroll on a video feed keeps a fourteen-year-old up past midnight. It does not materially improve that user’s life, and the people who built it largely restrict their own children from it. On the matrix, that is the bottom-right square.
Why 2026 changed the calculation
For a decade the hooked model lived in a world where the only scoreboard was engagement. If retention went up, the design was good. That world is closing.
The European Parliament adopted a resolution on addictive design by 545 votes to 12, naming infinite scroll, autoplay, and engagement-driven notifications as features that can harm wellbeing, especially for minors. The Commission’s cases against TikTok and Meta turned that political position into enforcement. Separate proceedings against Shein have zeroed in on reward-based engagement mechanics, points and incentives that nudge users to keep acting. The Digital Fairness Act moving through the EU is expected to codify limits on the sharpest of these patterns.
Notice what is being regulated. It is not a category of company. It is a category of design pattern, the exact patterns the hooked model teaches. A push notification is fine. A push notification engineered around a minor’s documented late-night usage is now evidence. A variable reward is fine. A variable reward tuned to override a stopping decision the user has already made is the thing under the microscope.
The distinction the regulators are drawing is the same one Eyal drew years earlier, and it is worth being precise about, because he has spent the years since arguing it. In Hooked and again in his 2019 book Indistractable, Eyal insists a habit and an addiction are not the same thing. A habit is a behavior done with little conscious thought. An addiction is a persistent, compulsive dependency that harms the user. His claim is that he wrote a book about building habits, not addictions, and that the two require different intent. Critics counter that once you deploy variable rewards at billion-user scale, the line between the two stops being something the designer controls. Both can be true. What changed in 2026 is that a regulator now gets to decide which side of the line your product landed on, and the fine is real.
Using the model without building a liability
I spent two decades in IT operations, a stretch of it in enterprise telecom, and later doing fractional operations work with founders through Ops Harmony. The pattern I have watched teams walk into, again and again, is treating an engagement metric as a goal instead of a proxy. Daily active users is a proxy for value delivered. When the team optimizes the proxy directly, it starts shipping loops that raise the number while the underlying value flatlines or declines. That gap is exactly where the manipulation matrix and the regulators are now both pointing.
If you are a product manager building with the hooked model in 2026, a few things follow.
Anchor the loop to a habit the user would defend. The test is not “will this raise retention.” It is “if the user understood exactly what we built and why, would they still want the habit.” A Duolingo streak survives that test for most people. A 1 a.m. autoplay chain does not. Run your core loop through the two matrix questions before you run it through an A/B test.
Instrument for compulsion, not just for engagement. The Commission faulted TikTok specifically for ignoring signals it could see: how late minors used the app, how often users reopened it, patterns that look less like habit and more like something the user cannot put down. If your analytics can show engagement, they can show compulsion. Look at both. The metric that should worry you is not low usage, it is usage that spikes at hours and frequencies a healthy habit would not.
Give the user a real stopping point. The remedies the Commission asked TikTok for, screen-time breaks, a recommender that does not treat “keep watching” as the only goal, an infinite scroll that is not actually infinite, are the design equivalent of a seatbelt. Building them in before a regulator requires it is both cheaper and better product. A loop the user can exit cleanly is a loop the user trusts.
Write down who this is for and whether you would use it. The Peddler quadrant is the trap most well-meaning teams fall into: they build a habit for a user they have never actually been. If nobody on the team uses the thing and means it, that is a signal, not a footnote.
The hooked model is not going away, and it should not. Habit-forming design is how genuinely useful products earn a place in a user’s day without buying it back through ads every week. The trigger, action, variable reward, investment loop is a real description of how behavior forms, and understanding it makes you a sharper product manager. What has changed is that the second half of the framework, the half about whether the habit deserves to exist, is no longer optional advice from the author. It is the line a regulator is now willing to draw for you, at 6% of revenue, if you will not draw it yourself.
Common questions about the hooked model
Is the hooked model manipulative?
The mechanics are neutral; the intent is not. The same loop that helps someone build a daily language habit can be pointed at keeping a teenager scrolling past midnight. Eyal’s own manipulation matrix is the honest test: does the habit materially improve the user’s life, and would you use it yourself. If the answer to either is no, you are closer to exploitation than to habit-forming design.
What is the difference between a habit and an addiction here?
Eyal’s distinction is that a habit is a low-effort behavior a user is glad to have, while an addiction is a compulsive dependency that harms them. In practice the line is not something the designer fully controls once variable rewards run at massive scale, which is why regulators have started drawing it from the outside.
Does the hooked model still work in 2026?
Yes, mechanically. Duolingo and dozens of others prove the loop still drives retention. What changed is the cost of building it carelessly. Engagement-driven patterns like infinite scroll and autoplay are now enforceable compliance issues in the EU, so the model needs to be paired with the ethics half Eyal shipped alongside it, not just the growth half.