Bridging Diagnosis and Repair. Zero Guesswork.

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Fixie AI

Timeline

Dec 2025 - Feb 2026

TEAM

Individual

MY ROLE

Behavioral Analysis

UX Strategy

UI & Interaction

Rapid Prototyping

AI Workflow

This case study focuses on closing the information gap between technicians and users through AI diagnostics. Discover how Fixie AI optimizes repair efficiency, boosting FTFR and reducing lead times.

GYUHO Lee © 2026

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Interact

Users don't just want a fast fix. They want a transparent process.

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01. Highlights

Process Support Guide:

Maximized FTFR,

Minimized Lead Time.

AI Diagnosis

From Guesswork to Data

Previously, users faced long wait times, relying on contacting technicians.
Fixie AI turns vague symptoms into clear, actionable diagnostics the moment a problem occurs.

DYNAMIC MATCHING

From Waiting to Visibility

Making the repair process visible with real-time updates and transparent timelines.

FAST RESPONSE

From Urgency to Action

Helping technicians review urgent jobs, prepare estimates, and respond with less friction.

02. Process

Human-Led,
AI-Accelerated Workflow.

Challenge

Logic Gaps & Generic Output

AI-generated plans often default to average solutions. They follow familiar patterns instead of adapting to nuanced contexts. In complex, human-centered scenarios, AI reasoning alone shows clear limitations.

Solution

AI for speed. Human for judgment.

I structured a workflow where human judgment guides key decisions, while AI accelerates execution. Clear intervention points maintain control and keep the process both systematic and adaptable. This is not about replacing human thinking, but knowing when to intervene.

Macro Framework

Phase 1.

Brain (Human)

  • Role - Empathy, Definition

  • Output - Problem Statement

Phase 2.

Spark (AI)

  • Role - Ideation, Variations

  • Output - Raw Layouts

Phase 3.

Hand (Human)

  • Role - Logic Check, Edge Cases

  • Output - Final Polish

4 Step AI–Human Collaboration

A structured execution model where AI accelerates production and humans safeguard strategic reasoning.

Step 1.

Research & Synthesis

  • Human: Conduct contextual interviews and gather qualitative signals to define initial direction.

  • AI: Analyze large-scale unstructured data to surface recurring pain points.

  • Outcome: Reduced bias and improved early-stage validation.

Step 2.

Information Architecture

  • Human: Define information priorities based on business goals and task flow.

  • AI: Detect logic gaps and edge cases across user scenarios.

  • Outcome: A resilient UX backbone with minimized blind spots.

Step 3.

Rapid Visual Exploration

  • AI: Generate fast low-fidelity UI explorations.

  • Human: Strategically reframe structures based on contextual realities and constraints.

  • Outcome: Production time reduced, focus shifted to meaningful adjustments.

Step 4.

Prototyping & Refinement

  • Human: Refined interactions based on psychological intent (clarity, urgency, trust signals).

  • AI: Provided feedback on interaction patterns and timing for smooth flows.

  • Outcome: A high-fidelity prototype that reduces cognitive friction.

03. Problem Space

Status: Pending. No ETA.

In traditional repair systems, users are often left in a state of “Pending.”

The real issue is not the breakdown itself, but the uncertainty built into the repair process.

While working at a restaurant in Berlin, I saw how opaque workflows and communication gaps turned even minor repairs into prolonged uncertainty.

UX Breakdown

  • Key Friction Points

  • Behavioral Pattern Analysis

  • Core Insight

Key Friction Points

Unclear Communication

Once an issue was reported, users often lacked clarity on the next step, response timing, or how their problem was being understood and handled.

Uncertain Timelines

Users often had no reliable sense of when a technician would arrive or when the issue would be resolved.

Lack of Real-Time Feedback

After the initial report, progress remained largely invisible to users.

How the Process Breaks Trust

When structural gaps turn into user impact.

💬

Language & Trust

Technical jargon and opaque procedures distance users from the process, weakening confidence in service quality.

“I wasn’t sure what was happening, but I had to pretend I understood.”

Process Anxiety

Not knowing when or how the issue will be resolved creates ongoing stress beyond the initial breakdown.

“I keep checking my phone. It feels like the whole day is on hold.”

📉

Operational Fallout

Lack of timely information and repeated technician visits disrupt daily operations and revenue.

“If one small part is missing, I lose another day of business.”

An information blind spot

"Users know the steps, but have no idea what is actually happening."

starry night sky over the starry night

Quick Insight

"It’s not a lack of will.

It’s the burden of manual tasks and missing data."

👨🏻‍🔧 Technician Interview

The Anatomy of Friction

This wasn’t just a psychological issue — it was a visibility failure in the system. Mapping the journey revealed two critical uncertainty peaks where the system failed to provide clarity.

Peak 1. The Confirmation Gap (Scheduling)

No clear confirmation at each stage. Users are forced to track progress themselves.

Peak 2. The Predictive Failure (On-site)

No real-time inventory sync. Technicians arrive without required parts. Repeat visits extend downtime and operational loss.

What Users felt

“When are they actually coming?”
“How long is this going to take?”
“Will it be fixed properly?”
“Do I need to keep following up?”

The Core Insight

From 'Fragmented Steps' to a 'Synchronized Loop'

When users turn to AI or others for answers, it is not because they are impatient. It is because they feel uncertain.

The issue is not slow service. It is the lack of reassurance.

Strategic Definition

The solution was redefined beyond a simple matching system into a predictable communication platform that removes the black box between diagnosis and repair.

Design Principle

'Zero Guesswork'

Users should never have to guess what is happening.

I reduced visual noise and made key information (status / time / steps) immediately clear. The goal was not smarter AI, but clearer information that enables confident action.

Integrated Strategy Map

Bridging Friction & Solutions

1:1 matrix unifying business impact and design principles to prevent narrative gaps.

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The Logic

Behind Solution

1.

Operational Inefficiency

Targeting a "Zero-Guesswork" Experience

  • Challenge: Information Asymmetry
    Technicians often arrive without enough information about the issue.

  • Strategy: AI Pre-Diagnosis [The Translator]
    Converts user descriptions into clear, structured data so technicians are prepared before arrival.

  • Goal: Maximizing FTFR
    Replaces blind visits with better-prepared service.

2.

Market Bottleneck

Improving Match Speed Through Incentives

  • Challenge: Supply-Demand Imbalance
    Matching delays during peak hours or for urgent tasks, leading to lost opportunities.

  • Strategy: Dynamic Time-Deal [The Matchmaker]
    Highlights high-value jobs in real time to encourage faster responses.

  • Goal: Reduce Delays in Matching
    Ensures urgent needs are met more quickly.

3.

Process Uncertainty

Building Trust by Minimizing "Anxiety Costs"

  • Challenge: High Anxiety Costs
    Users feel stressed due to a lack of visibility during the repair process.

  • Strategy: Real-time Status Tracker [The Zen Master]
    Provides a clear, trackable timeline that shows progress and builds confidence.

  • Goal: Build a Trust Loop
    Encourages repeat use by making the process transparent and predictable.

04. Strategy

AI Strategy & 3 Pillars
: From Uncertainty to Action

AI doesn't replace technicians; it replaces uncertainty.

Why AI?

Users already rely on AI to interpret problems in everyday situations. I introduced AI at the critical gap between Diagnosis and Action, where user anxiety peaks. Here, AI does not replace expertise.

It structures incomplete signals so users and technicians can operate with a shared understanding.

The AI Bridge : Structuring the Process

Step 1.

The Problem (Uncertainty)

  • User: High anxiety driven by "Blind Guesswork" about the problem's cause.

  • Technician: Inefficient, "Unprepared Visits" due to a systemic lack of site data.

Step 2.

AI Intervention (Structuring Signals)

  • Data Structuring: Converting fragmented, natural language inputs into Actionable Data.

  • Pre-Diagnosis Report: Providing experts with real-time guides to ensure a "First-Visit Fix."

  • Status Synchronization: Real-time syncing of the technician’s timeline for Full Process Visibility.

Step 3.

Human Action (Confident Execution)

  • User: Gaining "Controlled Reassurance" through transparent, real-time updates.

  • Technician: Arriving as a "Prepared Expert" with the exact parts and tools needed.

3 UX Design Pillars

Three strategic pillars to bridge the information gap through AI-driven design.

01.

The Translator

  • AI Data Structuring

Turning messy user input into clear, actionable signals.

Replacing blind visits with data-driven preparation to improve first-time fix rates.

  • Prepared Visits, Not Guesswork

02.

The Matchmaker

  • Dynamic Incentives

Adjusting incentives in real time to balance supply and demand.

Encouraging faster responses for urgent tasks during peak hours.

  • Reducing Market Congestion

03.

The Zen Master

  • Timeline Clarity

A clear, trackable timeline that builds trust and reduces uncertainty.

Reducing uncertainty to naturally drive repeat usage and long-term loyalty.

  • Building a Trust Loop

05. Exploration

Merging AI Logic with
Human Craft

Design Goal

To accelerate early design exploration with Google Stitch and enable greater focus on structural thinking and problem-solving.

AI Exploration,

Human Judgment

Google Stitch

Generated diverse IA-based layouts using AI to expand the exploration space. Compared and validated multiple structures to identify the most intuitive information architecture.

My Role

Redefined visual priorities and information hierarchy based on service logic. Refined AI-generated drafts to improve data clarity and real-world accessibility.

🍌 The Translator

From Repair Confusion

to Clear Action

Problem

Users face error codes, but are expected to diagnose problems themselves. This leads to confusion, misdiagnosis, and unnecessary visits.

AI Strategy

Instead of interpreting error codes, users describe issues in natural language.

AI translates this into structured diagnostic signals.

AI Assistant

Fixie

  • Analyze and diagnose the issue with specialized technical AI

  • Connect users with professional technicians when needed

Before matching users with a technician, the system proposes self-repair options.


This prioritizes user autonomy and potential cost savings.

Natural Language ➔ Diagnostic Clarity

How does the technician see this?

The diagnostic report is designed around these principles.

  • Confident Action

The report translates complex AI data into a clear, prioritized task flow, enabling immediate and confident action.

  • Zero Blind Visits

Pre-identified error codes and required parts increase first-time fix rates, eliminating unnecessary return visits.

Task Classification with codes

The AI-generated UI initially organized tasks by customer name, but this approach would become difficult to manage as task volume increases.

Unlike B2C apps that prioritize names or locations, technician dashboard required a more systematic indexing structure to manage multiple tasks without confusion.

I structured tasks using unique job codes (e.g., Job #4092), enabling technicians to quickly identify and manage multiple cases.

🍋‍🟩 The Matchmaker

Supporting Technician

Workflows

Independent technicians often rely on manual workflows and unstable customer acquisition.

To address this, I introduced a ride-hailing–inspired model, integrating automated matching and structured workflows directly into the dashboard.

Two modes, Standard and Urgent, structure workflow around Urgency.

Decision order: Urgency → Value → Fit

Urgency Drives Earnings

“ASAP” turns urgency into priority, keeping the marketplace fluid.

Standard: Customer pays €100 → €80 to technician

ASAP: Customer pays €100 → €88 to technician (+€8 incentive)

Made financial incentives visible upfront, encouraging faster acceptance through reduced platform fees.

  • Technicians: Immediate visibility of higher earnings

  • Customers: Faster matching and service

Deep Dive: Resolving UX

Conflicts

In usability testing of the main task management tab, the AI-generated UI revealed critical interaction conflicts that static views failed to surface.

Interaction Conflicts

  • Map vs. Card Gestures

Overlapping scroll areas made one-handed interactions unreliable.

  • Reduced Map Visibility

Large cards reduced map visibility, making routes harder to scan.

The interface needed to adapt to real field behavior, not just visual layout.

View AI Draft → Final UI

  • Separated Interaction Zones

Horizontal scrolling separated task browsing from map interaction, reducing gesture conflicts.

  • Adaptive Viewport

Once navigation starts, the task card minimizes to keep the route visible while remaining easy to revisit.

🍋 The Zen Master

Operational Transparency

The problem wasn’t only the repair itself, but the invisible process around it. A shared timeline made each step visible, reducing uncertainty for both users and technicians.

Customer Timeline

Technician Workflow

Design Decisions

  • Shared Visibility

Aligned user-facing progress with technician actions, creating a single source of truth and reducing uncertainty.

  • Reduced Workflow

Compressed technician updates into four core actions, enabling fast, reliable input in real-world conditions.

PING System

Our shop owner pointed out a recurring issue: customers struggled to receive timely updates without repeated phone calls.

"Can technician status be checked in just a few taps?"

AI Draft - Too many options, too little clarity

Side Effects :

More options ➔ More hesitation ➔ More confusion

Working with the shop owner, I removed unnecessary options and simplified the flow to the three most essential questions.

Response Windows & Accountability

When a technician does not respond within 10 minutes, the system steps in automatically.

Response Window Active

Quick response encouraged

Response Window Expired

Incentives removed, reliability affected

  • Response Incentives

Responding within 10 minutes preserves the urgency fee benefit. Delays automatically forfeit it.

  • Reliability Signals

Repeated delays weaken reliability signals, reducing visibility in future matching.

Digital Handshake

To close the repair process with clarity and trust, the system introduces a digital confirmation flow between technician and customer.


In Germany, invoices are often sent several days after the work is completed, without prior notice, leaving customers surprised and uncertain about the final cost.


As a result, the service often lacks a clear and smooth sense of closure.

Technician

Sets the Initial Estimate

Customer

Reviews and Approves the Estimate

Interview findings showed that technicians could provide a rough estimate after identifying the issue. This created an opportunity to align expectations early in the process.


So I designed the system to allow users to understand an early cost estimate before the repair began.

Once the repair is complete, the technician finalizes the work and submits:

  • AI-summarized repair report

  • Final invoice

By structuring the billing flow around early alignment and final confirmation, the system makes the closing stage easier to understand and accept.

Just a Few Extras

Personalized Service Logic

A clear entry point that guides users into the right flow based on their role.

Everything, Organized

Seamlessly managing every repair step, from active tracking to historical records.

See full breakdown

A Clear Final Step

Before paying, customers can review the final cost, completed work, and technician proof in one clear flow.

06. Design Impact

What the System
Now Enables

As this project is still in the MVP stage, live metrics are not yet available. Instead, prototype-based user testing was used to evaluate where the redesigned workflow could reduce delay, uncertainty, and friction. While the sample size was small, repeated observations revealed three meaningful patterns.

  1. Faster Diagnostic Alignment

After being matched with a technician, the time to receive an estimate was reduced from 11–14 days to under 30 minutes.

  1. Less Back-and-Forth, Faster Diagnosis

By replacing phone and email ping-pong with a structured AI intake flow, unnecessary back-and-forth was reduced and diagnostic feedback became significantly faster, shortening the process from 5–7 days to near real-time.

  1. Closing the Process, Faster and Clearer

Replacing Germany’s traditional invoice-based payment flow with in-app payment reduced service closure time from an average of 18 days to under 5 minutes.

AI Synergy & Efficiency

Integrating AI as a logical partner accelerated key stages of the design workflow, enabling faster exploration and deeper logic validation.

Early mockup production 3-4 weeks 1.5 weeks

a blue sky with some clouds

Systemic Scalability

Beyond individual repairs, designing a resilient ecosystem for professional service logic.

  • B2B Logic Expansion

Evolving into a SaaS platform for repair agencies to manage larger workforces and more complex service operations.

  • Data-Driven Ecosystem (Predictive Maintenance)

Using accumulated repair logs to anticipate recurring issues and enable more proactive service planning.

  • Vertical Domain Growth

Extending specialized diagnostic logic into high-stakes domains such as HVAC and Electrical Engineering.

What Mattered Most

Reflections

Field-Driven Logic: The UI was shaped around real-world technician constraints such as thumb-zone reach, movement, and one-handed use in the field.

AI–Human Synergy: AI accelerated structure and exploration, while human judgment refined clarity, trust, and decision-making.

Restoring Market Trust: Fragmented repair touchpoints were redesigned into a clearer service journey, making the final step easier to understand and trust.

Domain over Aesthetics: Meaningful solutions began with deeply understanding local service realities, not just making interfaces look polished.

System Thinking & Prompting: In the AI era, stronger product logic and clearer prompting became essential design skills.

Critical Discernment: The designer’s role was not only to use AI, but to identify weak logic, challenge assumptions, and refine outputs into reliable decisions.

One Last Thought.

The real value wasn’t AI alone.

It was how AI and human judgment worked together

to turn uncertainty into structure.

"NEXT ARCHIVE"

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DIRUNI