Eric Ries is a serial entrepreneur, a former student of Steve Blank, and author of the business bestselling book The Lean Startup. Eric Ries formalized the concept of lean startup, and lean methodology, and MVP which have become core business concepts in the startup world. Eric Ries is also the founder of LTSE (Long-Term Stock Exchange).
As pointed out by Eric Ries, a minimum viable product is that version of a new product which allows a team to collect the maximum amount of validated learning about customers with the least effort through a cycle of build, measure, learn; that is the foundation of the lean startup methodology.
In the Lean Startup, Eric Ries defined the engine of growth as “the mechanism that startups use to achieve sustainable growth.” He described sustainable growth as following a simple rule, “new customers come from the actions of past customers.” The three engines of growth are the sticky engine, the viral engine, and the paid engine. Each of those can be measured and tracked by a few key metrics.