In my presentation I let you know how I became a lean investor and lean innovation trainer and why I do not invest anymore in start-ups working the traditional way. However, this approach is not a cure-all. This means that an overwhelming majority of ideas for startups or corporates will fail regardless of how you approach it. My goal is to show you how to find this out as fast as possible and with the least effort. I point out the many pitfalls when working with Lean Startup/Lean Innovation and how to avoid them. The focus is on how to find out whether you have targeted the right customer segment and if not, how to iterate with problem & solution interviews between the Problem, Solution and the Customer Segment Fields of the Lean Canvas until you have reached the Problem/Solution Fit.