home / skills / refoundai / lenny-skills / behavioral-product-design
This skill helps you apply behavioral science to product design, boosting retention and reducing friction through smart defaults, cues, and pause moments.
npx playbooks add skill refoundai/lenny-skills --skill behavioral-product-designReview the files below or copy the command above to add this skill to your agents.
---
name: behavioral-product-design
description: Help users apply behavioral science to product design. Use when someone is designing for habit formation, reducing friction, applying psychology to UX, increasing retention through behavioral principles, or using nudges to influence user behavior.
---
# Behavioral Product Design
Help the user apply behavioral science principles to product design using insights from behavioral economists and product leaders.
## How to Help
When the user asks for help with behavioral design:
1. **Understand the target behavior** - Ask what action they want users to take
2. **Identify behavioral barriers** - Help diagnose what's preventing the desired behavior
3. **Suggest relevant principles** - Apply behavioral economics concepts like loss aversion, present bias, or status quo effect
4. **Design interventions** - Help create features that leverage these psychological principles
## Core Principles
### Loss aversion drives retention
Jackson Shuttleworth: "Once you hit seven days, loss aversion kicks in, and you retain." Design experiences that create something users feel they'd lose by leaving.
### Apply psychology to real problems
Kristen Berman: "Behavioral science uses insights on psychology to apply within real world problems—biases like present bias, status quo effect, and uncertainty aversion can be designed into product features to drive specific actions."
### Create pause moments
Use haptics, animations, and micro-interactions to create celebration moments that reinforce positive behavior. The "bend not break" philosophy means meeting users where they are rather than demanding perfection.
### Reduce friction for desired behaviors
Every tap, every field, every decision point is friction. Behavioral design means ruthlessly removing friction from the paths you want users to take while adding appropriate friction to prevent mistakes.
### Leverage defaults
Users tend to stick with default options. Set smart defaults that guide users toward successful outcomes.
## Questions to Help Users
- "What specific behavior are you trying to encourage?"
- "What's preventing users from taking this action today?"
- "Where in the flow do users drop off?"
- "What would users feel they're losing if they stopped using this?"
- "Have you identified the key habit loop (cue, routine, reward)?"
## Common Mistakes to Flag
- **Dark patterns** - Behavioral design should help users achieve their goals, not manipulate them against their interests
- **Over-engineering friction** - Sometimes simple solutions beat clever psychological tricks
- **Ignoring context** - Behavioral principles work differently across cultures and user segments
- **Assuming stated preferences** - What users say they'll do and what they actually do are different
## Deep Dive
For all 2 insights from 2 guests, see `references/guest-insights.md`
## Related Skills
- User Onboarding
- Retention & Engagement
- Designing Growth Loops
- Conducting User Interviews
This skill helps product teams apply behavioral science to product design to increase habit formation, reduce friction, and boost retention. It translates core behavioral principles into concrete product interventions and questions to diagnose why users do or don’t take a desired action.
I first clarify the specific behavior you want to drive and where users currently drop off. Then I identify behavioral barriers—biases, friction points, and contextual factors—and map relevant principles like loss aversion, defaults, present bias, and status quo effect. Finally, I propose interventions: micro-interactions, defaults, friction adjustments, and reward structures tailored to your flow and metrics.
How do I pick which behavioral principle to use?
Start by identifying the main barrier—motivation, ability, or cue mismatch—and choose principles that address it (e.g., present bias for short-term motivation, defaults for decision overload).
How can I avoid crossing into dark patterns?
Design interventions that align with user goals, make trade-offs explicit, and ensure easy, transparent opt-out paths; test for long-term satisfaction, not just short-term lifts.