One of the greatest challenges a manager can face is helping someone through a performance roadblock. This is especially true of those who have done well at every job they have ever done – for them, the idea of needing to change in order to succeed can be unpalatable, and in the end, holds them back from even higher performance.
The concept has been explained by The Peter Principle, and later in a humorous take on the concept by the The Dilbert Principle. In short, the rule is: employees tend to rise to their level of incompetence.
While one might want to shake their head at the depressing concept and move on, it doesn’t have to be that way; it is possible to overcome becoming obsolete, but requires acceptance and active effort from at least the employee as well as from someone willing to help them to the next level. It takes courage on both parts, and can be challenging for all involved, but is worth it. If left uncorrected, you will have an unhappy employee with the attendant low morale who affects others and decreases your organizations ability to work effectively. In the long-term, all parties would be happier if the problem were addressed.