Issues of RE in Waterfall | Resolved by RE in Agile |
Customer involvement: Customers are involved only during the beginning of requirement gathering and analysis [40] . | Customers are involved throughout the complete process. |
Prioritization of requirements: Complete requirements for the full project are prioritized upfront and the prioritization is kept up through the project lifecycle, and reprioritization is arduous [47] . | Priorities are setup for all iterations that offer opportunities for getting desirable results and customer satisfaction [48] [49] . |
Documentation: Totally emphasizes at properly gathering organizing and documenting all requirements and excludes any live meetings/conferences [14] . | User stories are concise and provide to-the-point explanation of user demands, obviate the need for maintaining long SRS documents. |
Requirements validation: Validation happens late in the life cycle. | Prototyping helps in providing the customer with a blueprint of the product, and therefore helps in validating the requirements [50] . |
Communication: It is a major factor in the delay and failure of software projects [40] . | It provides regular interaction with customer and among teams. |
Over-scoping of requirements: It is the cause of rework, which in turn causes further investment. | Developers receive a list of features that are constantly prioritized so the chance of having to repeat allocation in projects is minimized. |
Shall Argument: The worst thing of waterfall RE is “shall” argument i.e. system shall do it, etc. [46] . | Agile introduces the real time system. |