Waterfall: “The QA cycle involves authoring manual tests to match and cover the product requirements, authoring automated scripts to test the product features, updating regression scripts to test the defects that were found in past builds, and to run performance analysis on the build. … It [sic] requires larger toolsets to track test cases, testing results, performance testing, and automated scripting. Waterfall … requires a heavy investment in tools to get the job done because of the copious amount of work that needs to be tracked.”