The purpose of a user acceptance testing (UAT) phase is to validate the functionality and usability of a software product from the end-user's perspective. During UAT, actual users test the system to ensure it meets their requirements and performs as expected in a real-world scenario. This phase is crucial because it identifies any issues or shortcomings before the final deployment, significantly reducing the risk of user dissatisfaction. Successful UAT is a key indicator that the software is ready for launch, ensuring higher acceptance and adoption rates among users.