Danny Setiawan describes the stages startups go through and tools to validate hypotheses to get to product/market fit. The stages are problem/solution fit, then product/market fit, then growth. Tools include creating proto-personas, problem framing stories, user journey mapping, storyboarding, surveys, user interviews, and usability testing. Danny offers coaching, workshops, training, and support to help companies test hypotheses and get user feedback to progress through the stages.