The Lean Startup: Problem Interview

After listing your customer segment and value proposition assumptions on your Business Model Canvas, your next step is to test them by conducting a Problem Interview. 

Eric Ries’ build-measure-learn cycle takes a systematic approach to testing your business model.

By assessing customer segments on your BMC, the Problem Interview will help you validate any assumptions about your segments, as well existing problems, need, or wants.  

Following the build-measure-learn-cycle, the tasks that make up the Problem Interview should be repeated until you validate or invalidate your assumptions.  


The Build stage of the cycle involves creating a story and a problem interview form. The story should include the reasons why you came up with your product, as well as the three problems you believe your segments face. You will then tell your story during your problem interview with the identified customer segment, and then rank the three problems according to the following:

  1. The problem is painful and there is a need for a solution  
  2. The problem exists but is more discomforting than painful
  3. The customer is unaware or they don’t have the problem  


Once you got your story and Problem Interview form, define your test criteria and start interviewing. Begin by defining your goal, as well as the pass/fail criteria for the problem to be validated. For instance, customers will rank the problems in order of importance, and state whether the solution is a  “must-have”, “nice-to-have”, or “don’t have”. Afterwards, conduct at least 10 interviews with a partner, and take notes… lots of notes!  


Following the interviews, add up the results, analyze the data, and determine whether your assumptions have passed or failed your criteria. Once organized, reread the interview notes, and update your hypothesis based on these findings.

If you validate that your problem or need exists, persevere. But, if customers don’t have the assumed problem, then it’s time to consider scrapping your idea completely or pivoting.  

Pivoting involves revising your assumptions about your customer segment and their problems. If you discover a problem or unmet need that is more painful to the customer, adjust the problem for the same segment. This is called a Customer Need Pivot and will result in significant changes to your business model.

Keep in mind, that the number of interviews you conduct is variable. Therefore, talking to a larger sample of consumers will result in a better understanding of your assumptions. If you feel you need more data, continue interviewing and pivot until you validate those assumptions of yours.


Foster, P., & Giacomassi, R. (2015). Test Your Business Idea (1st ed.). Galeton, PA: The Business Therapist.

Ries, E. (2011). The Lean Startup: How Today’s Entrepreneurs Use Continuous Innovation to Create Radically Successful Businesses. New York: Crown Business.

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