SDLC Model - Software Development Life Cycle Waterfall Model Agile Model Waterfall Model Disadvantages of Waterfall Model It is difficult to estimate time and cost for each phase of the development process. Once an application is in the testing stage, it is very difficult to go back and change something that was not well-thought out in the concept stage. Not a good model for complex and object-oriented projects. Not suitable for the projects where requirements are at a moderate to high risk of changing. Agile Model Agile development model is also a type of Incremental model. Software is developed in incremental, rapid cycles. This results in small incremental releases with each release building on previous functionality. Each release is thoroughly tested to ensure software quality is maintained. Agile software development method emphasis on iterative, incremental, and evolutionary development. Delay In spite of the Model, still delay? Gap between development team and operations te