What technique is often used to validate assumptions made during the requirements phase?

User acceptance testing (UAT) is a crucial technique used to validate assumptions made during the requirements phase, as it directly involves end users in verifying that the system meets their needs and expectations. During UAT, users test the functionality of the system in a real-world scenario to ensure that requirements have been correctly understood and implemented. This process allows stakeholders to confirm that the assumptions about requirements are accurate and that the solution aligns with their business objectives.

While each of the other techniques is valuable in its own right, they serve different purposes. Prototyping is more focused on creating a preliminary version of the system to help users visualize requirements and provide feedback early in the development cycle. Documentation reviews are aimed at ensuring that the documentation accurately reflects the requirements but do not engage users in testing the functionality. Stakeholder interviews are primarily conducted to gather requirements and understand user needs rather than to validate the assumption after implementation. UAT stands out as the definitive method for validating these assumptions through hands-on user interaction with the system prior to final deployment.