In the fourth stage, the implementation is frozen and focus is primarily on quality. At the end of the stage, the product is delivered.
One of the goals of the last stage is to make the product sound and of high quality. No known critical errors are allowed in the final product. Sometimes, there is a gray area of definition between a product feature and a product error with the provider of the product, most often then not, providing features, while the customers viewing some features as errors.
The process is then repeated for the next version of the product.
The WaterSluice allows for phase interactions while at the same time setting firm temporal deadlines. The WaterSluice forces all four phases to communicate up front and to work together.
The WaterSluice software engineering methodology assumes the presence of five levels in a supporting software engineering environment as described in the appendix. Versioning is used to move the product from one version to another version by repeating the methodology for each version. Risk management is assumed throughout the process. The major components of analysis, the details in the design phase, the four main phases of implementation, and levels of testing proceed as previously described.