The Lean Startup

The Lean Startup by Eric Ries applies principles from lean manufacturing to the creation of new companies and products. Ries argues that most startups fail not because of poor execution but because they build things nobody wants, spending months or years in stealth mode developing a product based on unvalidated assumptions. His alternative is the Build-Measure-Learn feedback loop: launch a minimum viable product, gather real-world data, and pivot or persevere based on what you learn. The book introduces metrics that matter (actionable vs. vanity), innovation accounting, and the concept of the pivot. It has become the founding text of modern startup methodology and is required reading in accelerators, business schools, and product teams worldwide.