Lean Startup is an approach to developing products and businesses designed to minimize both time and cost. It is now a global movement led by author and software entrepreneur Eric Ries, who published the book Lean Startup after his own startup used the Customer Development methodology developed by Steve Blank. While details may differ, Lean Startup and Customer Development are very similar in overall approach.
The basic idea is that products or services designed without customer feedback often fail or need major revisions, both of which are very expensive. Instead, Lean Startup is a structured approach that 1) develops hypotheses or guesses about what customers want, 2) experiments to test those guesses, 3) iterates products as more is learned from customers, and 4) rigorously validates what is learned.
Lean Startup is rooted in the software industry, which allows for much more rapid product iteration than virtually any other industry. Nonetheless the Lean Startup methodology can be and has been adapted to many other products and services.
Lean Startup Is For Bootstrapping, Maybe Equity
While many companies that follow Lean Startup seek equity financing, we consider this a bootstrapping term because the end goal is expense minimization.