Incomplete user stories or requirements often lead to defects and delays in software development, as developers and testers must fill in gaps with assumptions, potentially resulting in inaccurate coding and testing. This challenge can be mitigated by QA testers engaging in creative problem-solving techniques such as mind mapping and prototyping to identify missing customer use case scenarios. These methods help visualize and analyze workflows, revealing gaps in provided requirements and allowing testers to anticipate issues before they arise. Effective communication with product managers and developers is crucial to resolving misunderstandings and ensuring a quality application release that aligns with customer expectations. While filling in missing details isn't officially the tester's responsibility, doing so proactively prevents defects and enhances user experience.