The manner in which employees are oriented and educated with their roles in the organization will depend on how well they are able to understand and fit in to their roles for the organization. While most people take on roles for the sake of being able to earn a living, the output and performance measures of such people will depend on how well they are able to understand their job.
Such is the purpose of having a job description in tow. With a detailed written overview of the tasks that are held in their responsibility as a guide to their daily routines, this will help in allowing them to have a better view of lined up expectations and understanding the importance of their job as well. Being an expert in their field of work is something that most organizations would indeed appreciate and the measurement of aligning themselves with the vision of the company is more than enough to ensure that they are in the write position and profession.
Barring any other excuses and reasons for being unable to perform according to corporate expectations, an organization is expected to operate efficiently and assess employee performance if they are indeed a perfect match for their employment. If not, the need to re-evaluate their roles and possibly be re-assigned to another department where they are more effective may be needed, if not, worst case is a separation of ways for the good of both parties.