Customer Discovery - Structuring an Interview

How can I conduct a better interview to uncover customer needs?

Here is some suggested structures:

1. Tell me about the last time _____

2. What was the hardest?

3. Why was that hard?

4. How do you solve it now?

5. Why is that not awesome?

Ground rules:

1. No pitching

2. No hypothetical questions - No "Would you...", "will you"