What I've realized about the Lean Startup methodology is that it only works for very specific businesses. Usually these are software-enabled service businesses

What I've realized about the Lean Startup methodology is that it only works for very specific businesses. Usually these are software-enabled service businesses (I.e. the software is not the essential part of the business). Standing up a pure SaaS business in 3 months just doesn't happen unless it's really straightforward and you already have it planned out.