- What problem are you solving?
- Can you state the problem clearly in two sentences?
- Have you experienced the problem yourself?
- Can you define the problem narrowly?
- Is the problem solvable?
- Who is your ideal customer?
- How often does your user have the problem?
- How intense is the problem?
- Are they willing to pay?
- How easy is it to find your customers?
It's really helpful to answer these questions before each iteration.
Inspired by the lecture «Building Product» by Michael Siebel