In a word, no. Every person is different. Every situation is different. Some people will come by themselves to the realization that the role in question is not for them. Others will never realise that without your help. A manager must assess the best way to proceed in every case, taking into account the particular situation, the personality of the employee, and, just as important, the likely consequences of taking no action.
If you’re in doubt, a good question to ask yourself is this: can you really allow the situation to persist much longer? What are the consequences for the business if the employee is allowed to remain in place? These consequences could include decline in productivity, poor staff morale, and also heightened stress on the part of the employee in question. In such circumstances, it becomes clear that the situation should be addressed.
If the employee is already aware that the job is not the right fit for him, the groundwork for the discussion will have already been laid. It is then a matter of steering the employee towards a conclusion that he has already – albeit not necessarily expressly – drawn. On the other hand, if the employee is unaware of his severe limitations in the role, the discussion is much more difficult.
And how to deliver the message? Most of the time, it suffices to have a quiet word. On some occasions, however, tougher measures are more appropriate. Over the years, I have had occasion to employ either technique, and it is always important to realise that the way you deliver the message is almost as important as the message itself.