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 Except when contractually required, the waterfall model has been largely superseded by more flexible and versatile methodologies developed specifically for software development.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 .
At this stage, Nissan’s marketing will be affected as several informative promotions and large monetary investments will be necessary to let the consumers know about the new electric car that is available on the market. Once the consumers learn about Nissan’s electric car, the product will enter in the next stage of market growth. Sales will increase and Nissan will make larger profits; however, the competition will also start to increasingly notice that the consumers are buying more electric cars. Then, the Nissan’s product will move to the next stage, market maturity; during this stage Nissan’s sales very likely will level off as there will be many competitors who will be selling electric cars. Finally, in the last stage of sales decline, Nissan will start replacing its Leaf model with newer models (Perreault, Cannon, & McCarthy, 2009).