I've conducted hundreds of customer interviews. Most of them were terrible.
Not because the customers were unhelpful, but because I was asking the wrong questions. Leading questions. Solution-first questions. Questions that confirmed what I wanted to hear rather than uncovering what I needed to know.
The worst part? I didn't realize how bad I was until years later.
The Customer Development Paradox
Here's the uncomfortable truth: most founders are terrible at customer interviews. We're builders, not researchers. We fall in love with our solutions, then unconsciously steer conversations toward validating them.
Classic mistakes I've made (and seen repeatedly):
- "Would you use an AI-powered solution for this?" (Leading toward a specific solution)
- "How much would you pay for this?" (Pricing before validating the problem exists)
- "This would save you time, right?" (Seeking agreement, not insight)
These questions feel productive but teach you nothing. Worse, they give you false confidence.
Why Customer Interviews Fail
1. Confirmation Bias is Your Default Mode Your brain desperately wants to hear "yes, your idea is brilliant." Every question you ask is subtly crafted to get that validation.
2. You Jump to Solutions Too Fast Engineers especially struggle here. We hear a problem and immediately start designing the fix, forgetting to deeply understand the problem space first.
3. You Don't Know What Good Looks Like Without seeing expert interviews, how would you know your questions are biased? It's like learning to code without ever reading good code.
4. Practice is Expensive Real customer interviews have real stakes. Practice on actual customers and you burn through your network while learning bad habits.
A Better Way to Learn
What if you could practice customer interviews with zero risk? Different personas, immediate feedback, and clear metrics on your performance?
I built this simulator because I needed it. After years of painful learning through actual interviews, I wanted to help others skip the expensive mistakes.
How to Use This Simulator
Start with Sarah Chen (CTO Persona) She's analytical, skeptical, and busy. If you can get valuable insights from her, you're doing something right. She'll punish you for wasting her time with obvious questions.
Focus on Problems, Not Solutions The highest-scoring questions are open-ended explorations of current workflows and past pain points. "Tell me about the last time..." beats "Would you use..." every time.
Watch Your Bias Indicators The simulator tracks whether your questions are leading, neutral, or assumption-heavy. Aim for 80% neutral questions. It's harder than you think.
Time Matters Real customers have real constraints. The timer isn't just a game mechanic—it's training you to be respectful and efficient.
What Great Customer Development Looks Like
After analyzing hundreds of interviews, the best ones share patterns:
The Magic Questions
"Tell me about your current process for [X]" Opens the door to understanding their world without imposing your assumptions.
"What happened the last time this was a problem?" Specific examples reveal more than general complaints ever will.
"What have you already tried?" Uncovers the solution space they've explored and why existing options failed.
"If you could wave a magic wand, what would this look like?" Gets them dreaming without you suggesting the dream.
The Flow
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Context Building (First 25%)
- Understand their role, responsibilities, and environment
- No agenda pushing, just learning
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Problem Discovery (Next 50%)
- Deep dive into workflows and friction points
- Specific examples, not generalizations
-
Priority Understanding (Next 20%)
- Which problems actually matter?
- What would they pay (time/money/effort) to solve?
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Solution Exploration (Final 5%)
- Only after understanding everything else
- Their ideas, not yours
Measuring Your Progress
The simulator gives you a score, but the real metrics that matter:
- Insight Density: How much did you learn per question?
- Bias Ratio: Neutral questions vs. leading questions
- Coverage: Did you explore the full problem space?
- Efficiency: Maximum insight, minimum time
Aim for consistent scores above 80. That's when you're ready for real customers.
From Simulator to Reality
The patterns you practice here translate directly:
Simulator: Different personas with varied communication styles Reality: Every customer is unique—adapt your approach
Simulator: Bias detection and scoring Reality: Self-awareness about your questioning patterns
Simulator: Time pressure Reality: Respect for busy customers
Simulator: Immediate feedback Reality: Record your interviews and score yourself
The Compound Effect
Better customer interviews create compound advantages:
- Product-Market Fit: You build what people actually need
- Faster Iteration: Clear signal vs. noise in feedback
- Better Positioning: You speak their language, not yours
- Stronger Conviction: Real evidence beats hopeful assumptions
Every percentage point improvement in interview quality translates to weeks saved in wrong directions.
Your Next Steps
- Run 10 simulated interviews across different personas
- Track your scores and identify weak areas
- Practice specific question types that score poorly
- Record one real interview and compare techniques
- Share what you learn with your team
The best product teams are learning machines. Customer development is the input that feeds everything else.
Stop guessing. Start discovering.
How do you approach customer interviews? What questions have revealed the most surprising insights? I'd love to hear your techniques and horror stories in the comments.