The Thrill Curve: Designing Peaks of Excitement Responsibly

Updated on 2026-02-20 • This page shares general design advice. It is not legal or clinical guidance.

A short moment that lives long

The clock hits 00:03. The screen blinks. A hush. Then the thing goes live. Your chest lifts, your hand moves fast, your eyes fix on one bright spot. For a brief slice of time, nothing else exists. Then it ends. You breathe again. You feel light, a bit wired, and you want to tell a friend.

We build digital things to make moments like this. A drop, a reveal, a flash sale, a live goal, a rare win. These peaks shape how people recall the whole ride. Done well, they delight. Done wrong, they harm. The hard part is not how to make a spike. The hard part is how to place it, size it, and cool it down—so people enjoy the high and still feel in charge.

This is the Thrill Curve. It is how arousal goes up and down over time in a flow. It has baselines, ramps, peaks, and a soft landing. This story is about how to design it with care.

Field note: what the Thrill Curve is

Think of the Thrill Curve as a simple line. It starts calm. It climbs with hints. It hits a peak at the right time. It drops back to calm fast and safe. That shape makes the whole session feel good, not just the top.

Why does this shape work? People judge an experience by its highs and its end. This is called the peak–end rule in UX. The idea comes from lab work on how we remember pain and joy. If you want the paper, see the original peak–end rule research.

There is more. A bit of stress can help focus, but too much stress hurts. This is known as the Yerkes–Dodson law. The sweet spot sits in the middle. The Thrill Curve aims to keep users in that middle band. It lifts them for a short time, then lets them rest.

The promise is clear: make peaks that people recall with joy, measure the load, and protect users who need more help to stay safe.

Side quest: a note from roller-coaster land

Ride designers do this well. They plan a slow climb. They pause for a view. Then they drop. After the drop, they add a calm turn. Your body gets a break. The next hill is smaller. The ride ends smooth. You step off smiling, not sick.

In apps, we forget the calm turn. We stack spike on spike. We push more taps, more lights, more noise. Then users feel spent. They close the app. Or worse, they keep going to chase the high. Lesson: build the valleys on purpose. Decompression is a feature, not a bug.

The design clinic: from cheap spikes to strong, fair peaks

Not all excitement is the same. Some tricks work fast but burn trust. Others take more craft but hold users well over time. If a pattern hides key info, steals time, or blocks choice, it is likely a dark pattern. The U.S. regulator has a full write-up on dark patterns. Here we look at better paths.

Mini before/after scenes

• Before: a timer pops up at random and screams “Only 60 seconds left!” After: a clear schedule shows when the drop starts. Users can add to calendar, snooze, or mute. Trust goes up. Stress goes down.
• Before: mystery loot chests with unclear odds. After: rewards on a set plan with posted odds up front. Users choose with eyes open.
• Before: pop-up wins flood the screen with loud sounds. After: soft cues that match user prefs. People still feel joy, and those who need quiet get it.

Red flags vs. green flags

• Red: fake urgency, hidden odds, near-miss tricks, no cool-down.
• Green: real dates and times, clear odds, clear exits, user-set limits, a calm end.

Informative table: common levers and guardrails

Anticipation countdown	Time scarcity raises focus; event is certain	More clicks before event	Anxiety, FOMO, compulsive checks	Cap use; show full schedule; snooze; no fake timers	Calendar invites; exact start times; opt-in alerts
Reveal moments	Joy when we resolve the unknown	Sharp engagement spikes	Variable-ratio pull if overused	Predictable cadence; post odds first	Tiered reveals on a clear plan; no pay-to-reveal
Social proof bursts	We copy the group; status cues pull	Faster cohort adoption	Pressure, herd effects on some users	Show totals, not spammy feeds; easy opt-out	Quiet proof: case notes, verified results
Rewards	Positive reinforcement	Short-term retention bump	Chasing, spend creep	Cooldowns; daily limits; tapering rewards	Earned milestones; user-set goals
Haptic/visual flair	Bright cues grab attention	Perceived excitement	Overstimulation	Reduced-intensity mode; user prefs	Minimal cues; gentle haptics
Near-miss framing	“Almost win” can drive retry	Retry lift (very short term)	Known link to harm	Do not use near-miss illusions	Show true results with clear framing

Practical note: If you build in iGaming or live events, do a public checklist of fairness and safety signals. That can include odds clarity, age gates, and help links. A simple list, kept fresh, builds trust over time.

Lab notes: how we measure, cap, and tell

We cannot manage what we do not measure. A good setup uses user-centered metrics and tech checks. For a UX lens, look at Google’s HEART framework. Below is a compact set you can use now.

What we measure

• Spike amplitude: how high a peak goes over baseline. Use clicks/min, views/sec, or HRV in lab tests.
• Time-to-baseline: minutes to return to normal after a peak. Goal: fast, calm recovery.
• Frequency of peaks: how many per session/day. More is not always better.
• Voluntary control rate: share of users who use snooze, mute, or limits.
• Disclosure comprehension rate: % of users who can restate odds or terms in one quick in-product quiz.

What we cap

• Set session limits. Add soft blocks after N high-intensity events.
• Set cooldowns (e.g., two minutes) after each strong peak.
• Throttle alerts. Respect quiet hours. Let users snooze with one tap.

What we publish

• Clear odds and terms. Use plain words and real numbers.
• Risk and help links in the same view as the call to act.
• Ethics and build rules. For a north star, see the ACM Code of Ethics.

A small, honest case (composite)

In a test across two live sports apps (composite example, not one brand), we added a two-minute cooldown after major peaks (goals, cash-out, flash promos). Results over 4 weeks:

• DAU: −1.2% (some users did fewer micro-sessions).
• Session length: +3.9% (people stayed, but with more calm time).
• Voluntary control rate: 24% used snooze or mute at least once.
• Support tickets about “too many alerts”: −31%.
• Self-set limits used: +18%.

Takeaway: small friction can lower noise and raise trust. Peaks still feel strong, but users feel in control.

Reality check: risk, rules, and the human side

Excitement is not free. For some people, strong peaks can push toward harm. See the UK’s gambling-related harms evidence review for a sober view of risks. Teams should build for the most at risk, not the median user.

Follow the law. If your app has age rules or KYC, handle it with care and with respect. The UK guidance on age and identity verification is a good place to learn the basics.

Also note the brain angle. Peaks tap into deep reward paths. The U.S. NIDA explains the brain reward system in simple terms. Read it to grasp why near-miss tricks or non-stop streaks can feel so hard to stop for some users.

Where we draw the line

Here is a plain ethical frame you can use in a team room:

• Intent: Does this peak serve a clear user goal, or just our KPI?
• Transparency: Can users see key info (odds, time, cost) before they act?
• Agency: Can they opt out, mute, or limit without pain?
• Proportionality: Is the intensity fit for the context and the age group?
• Reversibility: If we ship this and it harms, can we roll it back fast?

Use team rituals to make this real:

• Pre-mortem: “It is six weeks later. Our design caused harm. How?” Then fix those risks now.
• Ethics review: one person with veto on high-risk flows.
• Debias the roadmap: ask “Which users do we hear from least?” and test with them first.

If you do research with people, review the Belmont Report principles (respect, beneficence, justice). If you do content or ads with partners, follow the FTC endorsement disclosures. Say when you get a fee. Place the note by the link, not in a far page.

Practitioner’s cheat sheet: ship something safer this sprint

• Instrumentation: log peaks, time-to-baseline, and control use. Build a small dashboard.
• Cooldown logic: add a short cool-off after big spikes. Test 60–180 seconds.
• Copy audit: remove fake urgency. Replace with real times and clear odds.
• Odds UI: show odds or chance before action. Use plain words and numbers.
• Limits: add daily caps and session caps. Let users set their own too.
• Reduced-stimulation mode: dim lights, softer haptics, fewer effects.
• Help and age notes: put them near CTAs, not in the footer.
• Design process: map the problem with the Double Diamond process. Explore wide, then focus.
• Team drill: run a pre-mortem and one live review with a compliance lead.

Reader takeaways and a soft next step

Good peaks are not an accident. Plan the ramp. Cap the height. Design the way down. Measure the load. Tell users the truth. Give them control. Ship help links. Then check your work and adjust.

If you study real products to learn what clear odds and good help links look like, you can scan popular real-money gaming platforms to see common patterns. Note: some links on such sites may be affiliate links. Please read their disclosures. Gambling has risks and legal limits. If you or someone you know has a problem, seek help in your region.

Simple, plain help links (add the right ones for your region)

• US: 1-800-GAMBLER (call or text). Visit 1800gambler.com.
• UK: BeGambleAware.org, 0808 8020 133.
• Canada: ConnexOntario.ca, 1-866-531-2600.

FAQ

What is the Thrill Curve and how is it different from the peak–end rule?

The Thrill Curve is the shape of arousal in time. It shows a calm start, a build, a peak, and a soft end. The peak–end rule is a memory rule. It says we judge by the high point and the end. The Curve helps you design the flow. The rule helps you judge how people may recall it.

How do you measure a “peak” without causing harm?

Use proxy metrics like clicks/min or views/sec to find peaks. Track time-to-baseline to see how fast users calm down. Add cooldowns and limits if peaks stack up or if time-to-baseline grows. Ask a one-line odds quiz to check if users get key info. Stop tests if risk flags rise.

Which dark patterns should teams avoid when designing excitement?

Avoid fake timers, hidden odds, hard-to-close pop-ups, near-miss tricks, and forced loops after “no.” Use real time, clear odds, soft exits, and one-tap controls instead.

What guardrails help reduce risky user behavior?

Use session caps, daily caps, and cooldowns. Put odds first. Use a reduced-stimulation mode. Add risk prompts on fast loss spikes. Keep help links near CTAs. Log and review risk flags each week.

How often should thrill events occur in an app or site?

Match the pace to the task. For fast live play, peaks can be more often, but each one should be short and spaced. For calm tools, peaks can be rare. Try this start: one strong peak per 5–10 minutes with a 2–3 minute cooldown, then adjust to your data.

Copy patterns you can paste and tune

• Timer copy (ethical): “Opens at 4:00 PM local time. Add to calendar. Snooze alerts for today.”
• Odds copy: “Chance to win: 12%. Learn how we calculate odds.”
• Limit copy: “Set a daily limit. Change it anytime.”
• Help copy: “Need a break? Take one. Support is one tap away.”

A tiny lab sketch (text-only)

Plot a line for 10 minutes. Mark 0–2 min: calm. 2–3 min: cues start. 3–4 min: peak. 4–6 min: cooldown. 6–10 min: calm with small beats. Add notes: amplitude +40% over baseline; time-to-baseline 2.5 min; one peak per 10 min; 22% used snooze. This is a healthy shape.

Build notes for your backlog

• Data: add an event for “high-intensity moment” and a flag for “cooldown start.”
• Controls: add a visible “Snooze alerts for 1 hour” button near any timer or promo.
• Design tokens: set a reduced-stimulation theme with smaller motion and softer sound.
• Safety net: if rapid-loss or rapid-bet is seen, show a speed bump with links to limits and help.

Compliance and trust basics

• Show age rules and KYC in clear words. Keep privacy short and linked.
• If you get fees from links, say so near the link. Keep the note in the same view.
• Publish change logs for odds or rules. Put a date on each page. This page has one at the top.

Team rituals that help

• Weekly ethics stand-up: one risk story, one fix shipped.
• User council: three power users and three at-risk users. Hear them each month.
• Post-peak review: after any special event, look at time-to-baseline, control use, and tickets. Share one thing you will change.

Design smells to watch for

• Peaks stack with no valley.
• Odds or costs show after the tap, not before.
• “No” is hidden or takes more steps than “Yes.”
• Pop-ups block help links.
• Scores of users mute alerts or uninstall after a big event.

A note on culture and language

Excitement has many faces. Some users cheer. Some go quiet. Some see risk sooner. Use plain words. Avoid slang like “hot streaks.” Test copy with people who do not speak your team’s first language. Check that help links read well with a screen reader.

Sample targets (adjust to your context)

• Time-to-baseline: under 3 minutes after any major peak.
• Control use: at least 20% of engaged users try snooze, mute, or limits.
• Disclosure quiz: 80%+ get odds or key terms right on first try.
• Peak frequency: no more than one strong peak every 5 minutes (unless live play demands it, then add cooldowns).

What to do when a test goes wrong

Kill switch first. Remove the spike. Post a short note: what happened, what changed. Review tickets fast. Offer help. Update your guardrails list and share it with the team.

About the author

Alex Morgan is a UX lead who has worked on regulated products for 10+ years. Alex has led teams on live sports, fintech, and games with a focus on safe design.

Reviewed by: Jamie Lee, Compliance Advisor (responsible gambling and privacy).

Sources and further reading

• peak–end rule in UX
• original peak–end rule research
• Yerkes–Dodson law
• dark patterns
• HEART framework
• ACM Code of Ethics
• gambling-related harms evidence review
• age and identity verification
• Belmont Report principles
• FTC endorsement disclosures
• brain reward system
• Double Diamond process

Compliance note and help

Gambling involves risk and is age-restricted by law. Follow local rules. If you or someone you know has a problem, seek help in your region (see links above). If this page links to any site that earns fees from referrals, a note should appear near that link.