In which phase of the SDLC does User Acceptance Testing commonly occur?

User Acceptance Testing (UAT) is primarily conducted during the Construction phase of the Software Development Life Cycle (SDLC). This phase involves the actual development of the software based on the requirements gathered in the earlier phases. During Construction, developers create the software components, and once these components are built, they are tested to ensure they meet the specified requirements.

UAT occurs towards the end of the Construction phase, just before the software is finalized and delivered. This testing is crucial as it involves end-users who validate that the system meets their needs and expectations based on real-world scenarios. Successful completion of UAT indicates that the software is ready for deployment and aligns with user requirements.

In contrast, the Initial design phase focuses on planning and outlining the architecture of the system without actual implementation, which does not involve user testing. The Analysis phase is centered around gathering and defining requirements rather than testing the built software. Finally, the Maintenance phase occurs after the software has been deployed and involves patches, updates, and support, rather than initial user acceptance verification. This context underscores why UAT fits specifically within the Construction phase, as it assesses the completed product before it goes live.