The waterfall model is a traditional engineering approach applied to software engineering. A strict waterfall approach discourages revisiting and revising any prior phase once it is complete. This "inflexibility" in a pure waterfall model has been a source of criticism by supporters of other more "flexible" models. It has been widely blamed for several large-scale government projects running over budget, over time and sometimes failing to deliver on requirements due to the Big Design Up Front approach. Except when contractually required, the waterfall model has been largely superseded by more flexible and versatile methodologies developed specifically for software development. See Criticism of Waterfall model .
Progress in manufacturing is measured by the production of high quality goods. The unit of progress for Lean Startups is validated learning-a rigorous method for demonstrating progress when one is embedded in the soil of extreme uncertainty. Once entrepreneurs embrace validated learning, the development process can shrink substantially. When you focus on figuring the right thing to build-the thing customers want and will pay for-you need not spend months waiting for a product beta launch to change the company's direction. Instead, entrepreneurs can adapt their plans incrementally, inch by inch, minute by minute.
Online Scrum Master training is available in the Scrum Training Series , a free collection of entertaining e-learning modules covering an Introduction to Scrum , the Backlog Grooming Meeting , the Sprint Planning Meeting , the Daily Scrum Meeting , the Sprint Review Meeting , and the Sprint Retrospective Meeting . You can download the 6-page Scrum Reference Card or learn what the Scrum Master does. In person Certified Scrum Master training , typically using group immersion activities and case studies, is also available all over the world.