Designers often talk a lot about "reducing friction" as a goal to strive for. We want smooth flows, instant loads, and intuitive interfaces. At least we think we do.

But what if I told you that sometimes, the secret to engagement is actually adding a little bit of psychological itching to the interface.

Enter the Zeigarnik Effect. The Zeigarnik Effect states that people remember uncompleted or interrupted tasks better than completed ones. An "open loop" creates a specific kind of cognitive tension. The human brain hates ambiguity and it wants to close the loop.

The Zeigarnik Effect is named after Bluma Zeigarnik, a Soviet psychologist who first identified the phenomenon in the 1920s. While studying under Kurt Lewin, she observed that waiters were remarkably good at remembering unpaid orders, but quickly forgot them once the bill was settled.

Her experiments later confirmed the pattern: unfinished tasks create a kind of low-level mental tension that keeps them active in memory. Once the task is completed, that tension dissolves, and so does the cognitive attention attached to it.

This is why errors and bugs take up so much mental space, while software that just works tends to vanish from our memory in days.

In UI design, this translates to one thing: A user is more likely to interact with an interface if they feel they are in the middle of a process, rather than at the start of one.

Implementing the "Open Loop" Pattern

Here is how you can translate this psychological quirk into tangible UI elements.

1. The "Endowed Progress" Effect (The Head Start)

If you give a user a punch card with 10 slots, they are slow to start. If you give them a card with 12 slots, but 2 are already stamped, they fill it out much faster. Why? Because the task is already underway. The loop is open.

Never show a "0% Completed" state if you can help it. When a user signs up, the "Sign Up" process itself should count as Step 1. By the time they hit the dashboard, your onboarding wizard should say "25% Complete." They aren't starting a mountain climb, they are already on the path.

This status bar is much less stressful overall than this one:

However, you also don't want to tip over into 99% complete territory either, as that can backfire.

If a user thinks that they are essentially done with signing up, they might settle with 90%+ being enough.

2. The Multi-Step Form (The Wizard)

Giant forms are terrifying. They look like work. But breaking a form into steps leverages the Zeigarnik Effect much better.

Once a user clicks "Next" on Step 1, they have opened a loop. Abandoning the form at Step 2 feels psychologically more painful than never starting it, because they are leaving a task "unfinished."

Use a clear Stepper UI. Visually show the incomplete steps ahead (usually grayed out). This acts as a visual promise of closure. Don't just number them "Step 1, Step 2." Label them with the value they provide: "Account > Personalization > Launch."

For me personally, when I see a giant form that I need to fill out before I can continue, I immediately look for the "Skip" button. And this is mainly because I'm not quite "sold" on the idea just yet. I just want to check things out without committing too much time.

3. The "Content Teaser" (The Truncation)

This is the classic news site pattern. You see a headline and the first paragraph, followed by a "Read More" button or a blur.

This is a literal open loop. The sentence is cut off. The story is incomplete. Your brain demands the rest of the pattern.

Be careful with the "fold." If your design looks too complete above the fold, users might not scroll. Deliberately cutting off content (visual hints of more text, half an image) signals to the brain that "there is more to this pattern," prompting the scroll.

News sites have gotten incredibly efficient at this and can cut off the text at a crucial part in the story, leaving the loop opened for longer and slowly eating at you after you decide to leave.

4. Gamification and "Collection" UI

Badges, trophies, and empty slots are pure Zeigarnik fuel. An empty trophy case creates tension. A grayed-out badge that says "Locked" is much more compelling than a badge that doesn't exist yet.

Show the empty states. Don't hide the achievements the user hasn't earned yet. Display them as "incomplete tasks" to trigger the desire to collect them all.

Reddit is a great example for this. I personally chased the streak dragon for over a year, before I stumbled and had to start over, at which point I completely abandoned the race.

The Dark Pattern Warning

There is a fine line between "motivating users" and "doom scrolling." One can be a useful tool to increase engagement and the other is an unethical visual hack to trick users into doing things they aren't aware of, aka, a dark pattern.

Social media feeds are the weaponized version of this effect. Because the feed is infinite, the loop never closes. This creates an addictive cycle rather than a satisfying one.

Ethical Design Consideration: Always provide a clear "State of Completion."

• Good Zeigarnik: A checklist that reaches 100% and celebrates (Loop Closed = Dopamine Hit).
• Bad Zeigarnik: An infinite scroll or a notification badge that never clears (Loop Forever Open = Anxiety).

I'll close by saying that good design is indeed difficult. In order to implement the design elements seen in the examples above, you need to create trophy systems, track status states, show timed notifications, etc.

All extra work that often times takes longer than implementing the more important payment systems or innovative features.

But they are equally as important. They push users to complete profiles, to stay engaged with your product and to overall just have a better experience.

So if you haven't been using these elements in your projects, hopefully this inspires you to spin up a point system and to start increasing engagement with your users.