Customer Discovery & Validation
The definitive guide to understanding your customers before you build. Learn the frameworks, questions, and signals that separate successful startups from the 90% that fail.
“The biggest risk is building something nobody wants. Customer discovery is how you eliminate that risk before you waste months building.”
The #1 reason startups fail is "no market need" — not competition, not running out of money, not team issues.
The Four Phases of Customer Discovery
Problem Discovery
Validate that the problem exists and is painful enough to solve
Solution Validation
Test your proposed solution with target customers
MVP Definition
Define the minimum feature set to test your hypothesis
PMF Signals
Measure early indicators of product-market fit
Problem Discovery Interviews
The goal of problem interviews is to validate that a real, painful problem exists — and that your target customer is actively trying to solve it. You're not pitching or testing solutions. You're listening and learning.
The Mom Test: Three Rules
From Rob Fitzpatrick's essential book on customer conversations:
Ask about problems they've experienced, not hypothetical reactions to your solution.
“Tell me about the last time...” reveals real behavior. Future promises are worthless.
You should be talking 20% of the time max. Every word you say is a missed learning opportunity.
Problem Interview Question Bank
Context & Background
- +“Tell me about your role and what a typical day/week looks like.”
- +“What are the biggest challenges you face in [area]?”
- +“Walk me through the last time you experienced [problem].”
Problem Deep-Dive
- +“How often does this problem occur?”
- +“What triggers this problem?”
- +“What happens if this problem isn't solved?”
- +“On a scale of 1-10, how painful is this problem?”
Current Solutions
- +“How are you solving this problem today?”
- +“What do you like about your current solution?”
- +“What's frustrating about your current approach?”
- +“How much time/money do you spend on this currently?”
Buying Behavior
- +“Have you looked for solutions to this problem?”
- +“What would make you switch from your current solution?”
- +“Who else is involved in decisions like this?”
- +“What budget do you have for solving this?”
Sample Problem Interview Script
Copy and adapt this script for your interviews:
[Opening - 2 min]
“Thanks for taking the time. I'm researching how [target role] handles [problem area]. I'm not selling anything — just trying to understand your experience. Everything you share is confidential. Mind if I take notes?”
[Context - 5 min]
“To start, tell me about your role. What does a typical week look like for you?”
“What are the biggest challenges you face in [area]?”
[Problem Deep-Dive - 15 min]
“You mentioned [problem]. Tell me about the last time that happened.”
“What triggered it? What happened next?”
“How did you try to solve it?”
“What was frustrating about that approach?”
“On a scale of 1-10, how painful is this problem for you?”
[Current Solutions - 5 min]
“What tools or processes do you currently use to handle this?”
“How much time or money do you spend on this today?”
“Have you looked for better solutions? What did you find?”
[Wrap-Up - 3 min]
“Is there anything else about [problem area] I should have asked?”
“Who else do you know who deals with this problem? Would you be open to introducing me?”
“Thanks so much. Can I follow up if I have more questions?”
Finding Interview Participants
| Channel | Pros | Cons | Tips |
|---|---|---|---|
| Targeted by role, industry, company size | Can feel cold, low response rates | Personalize heavily, mention mutual connections, keep ask small | |
| Warm Intros | Higher trust, better conversion | Limited scale, network dependent | Ask investors, advisors, friends for intros to their network |
| Communities | Pre-qualified interest, engaged users | May violate community rules, selection bias | Slack groups, Discord, Reddit, industry forums - give before you ask |
| Existing Customers | Already engaged, easier to reach | Biased toward current solution | Great for solution interviews, less ideal for problem discovery |
| Paid Recruiting | Fast, scalable, diverse | Expensive, may get professional respondents | Use Respondent.io, UserInterviews.com - screen heavily |
LinkedIn Outreach Template
Hi [Name],
I noticed you're [role] at [company] — I'm researching how [target role]s handle [problem area].
Would you have 20 minutes for a quick call? I'm not selling anything — just trying to learn from practitioners like you.
Happy to share what I learn from other [role]s as a thank you.
Best,
[Your name]
Warm Intro Request Template
Hi [Connector],
I'm doing research on [problem area] and trying to talk to [target role]s at [company type].
I noticed you're connected to [Name] — would you be comfortable making an intro? Just looking for a 20-min conversation about their experience.
Here's a blurb you can forward:
“[Your name] is researching [topic] and would love 20 min to learn from your experience. No pitch — just research. Interested?”
Solution Validation
Only after validating the problem should you test solutions. The goal is to find the simplest thing you can build that customers will pay for — not your dream product.
Solution Interview Goals
- +Validate that your solution addresses the core problem
- +Identify must-have vs. nice-to-have features
- +Test willingness to pay and price sensitivity
- +Understand the buying process and stakeholders
- +Get commitments: pre-orders, pilots, LOIs
What to Show (Not a Full Product)
- +Wireframes/Mockups: Low-fidelity screens showing key flows
- +Clickable Prototype: Figma/InVision prototype of core experience
- +Landing Page: Value prop + signup to test demand
- +Concierge MVP: Manual delivery of the service to test value
- +Wizard of Oz: Fake automation with humans behind the scenes
Solution Interview Questions
After Demo
- “What's your initial reaction?”
- “How would this fit into your current workflow?”
- “What's confusing or unclear?”
- “What's missing that you'd need?”
- “What would you remove or simplify?”
Commitment Testing
- “If this existed today, would you use it?”
- “What would you pay for this?”
- “Would you sign up for our pilot program?”
- “Can I put you on our early access list?”
- “Would you pre-pay for early access?”
Defining Your MVP
Your MVP should be the smallest thing you can build to test your core hypothesis. It's not a crappy version of your vision — it's a focused test of your riskiest assumption.
List Your Assumptions
Write down every assumption your startup depends on. Who's the customer? What problem? Why now? Why you?
Rank by Risk
Which assumption, if wrong, would kill the business? That's your riskiest assumption. Test it first.
Design the Smallest Test
What's the fastest, cheapest way to test this assumption? That's your MVP scope.
The MVP Scoping Framework
Must Have (Ship Blockers)
- + Core value proposition delivery
- + User can complete primary job-to-be-done
- + Basic auth and data security
- + Way to collect feedback
Should Not Have (Cut Ruthlessly)
- - Edge case handling
- - Admin dashboards
- - Multiple user roles
- - Integrations
- - Mobile apps (unless core)
- - Notifications/emails
- - Settings/customization
“If you're not embarrassed by the first version of your product, you've launched too late.” — Reid Hoffman
Product-Market Fit Signals
Product-market fit isn't a binary state — it's a spectrum. These signals help you gauge how close you are and what to focus on next.
The Sean Ellis PMF Survey
Ask users: “How would you feel if you could no longer use [product]?”
| Signal | Strong PMF | Weak PMF | Benchmark |
|---|---|---|---|
| Organic Word-of-Mouth | Users actively recommend without prompting | Only share when directly asked | 40%+ of new users from referrals |
| Retention | Users return daily/weekly without prompts | Need constant reminders to engage | D7 retention >25%, D30 >15% |
| Willingness to Pay | Users ask how to pay, upgrade requests | Only use if free, churn at any price | >5% free-to-paid conversion |
| Usage Depth | Users discover and use advanced features | Only use basic features once | Power users emerge naturally |
| Disappointment Test | "Very disappointed" if product gone >40% | "Somewhat disappointed" majority | Sean Ellis PMF survey >40% |
| Pull vs Push | Users ask for features, integrations | Need to convince users of value | Inbound feature requests > outbound |
8 Common Customer Discovery Mistakes
Pitching Instead of Listening
You spend the interview selling your solution instead of understanding their problem.
Follow the 80/20 rule: listen 80%, talk 20%. Never mention your solution in problem interviews.
Leading Questions
"Don't you think it would be great if..." leads them to your desired answer.
Use open-ended questions. Ask "how" and "why" instead of "would you" or "do you".
Asking About the Future
"Would you use a product that..." People can't predict their future behavior.
Focus on past behavior. "Tell me about the last time..." reveals actual patterns.
Confirmation Bias
Only hearing evidence that supports your hypothesis.
Actively seek disconfirming evidence. Ask "What would make this NOT work for you?"
Too Few Interviews
Stopping after 5 interviews because you "got the signal."
Do 15-20 problem interviews minimum. Look for patterns across multiple conversations.
Wrong Participants
Interviewing friends, other founders, or people outside your target market.
Be ruthless about screening. Define your ICP and only talk to exact matches.
No Note-Taking System
Relying on memory or scattered notes you can't analyze.
Record (with permission), transcribe, and tag insights systematically.
Skipping to Solution
Jumping to solution interviews before validating the problem.
Problem validation must come first. Don't show solutions until problem is confirmed.
Analyzing Your Interview Data
What to Track
- +Problem frequency: How often does this come up?
- +Pain intensity: Average score 1-10
- +Current solutions: What are they using today?
- +Budget/spend: What do they pay currently?
- +Quotes: Exact words they use
Pattern Recognition
- +Look for themes mentioned by 5+ people
- +Note surprising or contradictory findings
- +Identify segments with similar needs
- +Watch for “hair on fire” problems
- +Trust behavior over opinions
Problem Validation Checklist
Before moving to solution validation, confirm:
Get the Customer Discovery Toolkit
Download our complete toolkit including interview scripts, analysis templates, recruiting outreach templates, and the PMF survey template.
Interview Scripts
Analysis Template
Outreach Templates
PMF Survey
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Continue Your Research
Essential Books on Customer Discovery
The Mom Test
Rob Fitzpatrick
The essential guide to customer conversations. Short, practical, and immediately actionable.
Talking to Humans
Giff Constable
A practical guide to customer development interviews with templates and examples.
The Lean Startup
Eric Ries
The foundational text on validated learning and build-measure-learn loops.