Risk assessments are most effective when performed at each stage of the system development life cycle (SDLC). The SDLC is a framework that defines the phases and activities of developing, implementing, and maintaining a system. The SDLC typically consists of the following stages: initiation, planning, analysis, design, development, testing, implementation, and maintenance. Performing risk assessments at each stage of the SDLC helps to identify, analyze, and evaluate the risks that could affect the system objectives, requirements, functionality, quality, or performance. Performing risk assessments at each stage of the SDLC also helps to select and implement the appropriate risk responses, such as avoiding, transferring, mitigating, or accepting the risks. Performing risk assessments at each stage of the SDLC also helps to monitor and report the risk status and performance, and to update and adjust the risk assessment and response as the system changes or evolves. Performing risk assessments before system development begins, at system development, or during the development of the business case are not as effective as performing risk assessments at each stage of the SDLC, as they are either too early or too late, and they do not capture the full scope and complexity of the system risks. References = CRISC Review Manual, 6th Edition, ISACA, 2015, page 49.