The study looked at how giving employees clear job descriptions can affect their performance before and after. They observed 17 mechanics at a company. They used interviews, surveys, observations, and ratings to gather information on job descriptions and performance. Using a statistical test, they found that employee performance improved significantly after receiving job descriptions compared to before. This means that providing clear job descriptions helps workers understand their tasks better, their responsibilities, and the limits of their authority, leading to better performance. In the future, having two evaluators can make performance assessments more objective.