Your first interviews will be experimental. During these, you’ll develop your interview format and refine your questions.

After the interviews, you should be able to answer the following questions:

• How does the user currently solve the problem?
• If a product that could solve the respondent’s problem existed, would they spend money on it?
• Does your solution fit into the respondent’s lifestyle? Will they use it?

If you don’t have answers to these questions, try modifying your questions.

After 4-5 interviews, you’ll start to see if the problem truly exists. If no one gets excited about your idea, the problem might not be significant, or you might have the wrong target audience.

In this case, try shifting to a different audience segment. If this still doesn’t validate your hypothesis, congratulations! You’ve gained valuable insights with minimal risk. What's next? Move on to testing the next hypothesis!

After 10 interviews, you’ll notice similar behavior patterns. You’ll start to understand in what situations your target audience encounters the problem and why it happens.

There’s no exact number of interviews you need to conduct. When you stop hearing new information and start forming a clear idea of what to include in your MVP, you can wrap up CustDev.

The next stage in your action plan is modeling the economics. Yes, you’ve found a solution to the problem, but will the project be profitable?

At this step, estimate the required income and expenses: how much it will cost to create the product and attract customers. If the economics work out even in the most pessimistic scenarios, you can proceed with development.

To calculate this, you need to choose metrics that characterize the project’s economics and determine their values. Typically, key metrics include LTV (lifetime value of the customer) and CAC (customer acquisition cost).

For the economics to work out, LTV should be greater than CAC. But where do you get these values? This is where creating an MVP comes in. There’s a common misconception that an MVP is a stripped-down version of the planned product. This isn’t true. An MVP can be anything that allows you to test your hypotheses and get metric values.

The MVP should include only the functionality necessary to test the viability of the idea.

Essentially, it might not even be an app. A presentation or a landing page might be sufficient—anything that promises value to the user.

You can consider the MVP stage complete when the product’s metrics meet the target values for this stage. This confirms that the product is needed and you can move on to the next stage—finding scalable user acquisition channels.

After conducting interviews and analyzing the information, you need to answer the main question: "Is the hypothesis correct?"

Signs that confirm your hypothesis:

• Respondents acknowledge the problem.
• Respondents believe the problem can and should be solved.
• It’s up to the respondents, not others, to solve the problem.
• Respondents invest resources in solving the problem.

Of course, the result of CustDev isn’t a guarantee of product success in the market. It serves a different purpose—determining which hypotheses need to be tested further using an MVP.

Based on the insights from CustDev, determine the functionality to include in your MVP and start developing it. We discussed how to do this in another article.