Agile and Lean Development
In the eighties, the backlash against waterfall methodologies was growing. Large defense and IT projects were failing with growing frequency. This led to numerous books and articles defining better practices. Some of these methodologies, such as evolutionary delivery, promoted incremental development of products using iterations. Each iteration contained a slice of all the phases of development instead of development being spread out over an entire waterfall cycle. The iterations could be as short as a week but included analysis, design, coding, integration, and testing within that time frame rather than spreading each of them out over years as they could be on a waterfall project.