There is no reason why the execution of a project or task should not be handled internally, if the appropriate staff to scrutinize conditions, with sufficient time and resources, the appropriate knowledge and the ability to investigate things in a critical and unbiased way is available.
Consulting services should be taken into consideration if the task is completely new and unique, particularly complex and/or time is limited. To increase the workload of employees without adequate internal resources will lead to negative consequences. The results often are slow project progress, inferior quality and exaggerating demands on employees involved.
In case of free capacity within the company, the question of how employees are engaged in periods without special projects should be investigated.
As a matter of fact, using external consulting should not only be a question of time but particularly one of appropriate know-how. Nobody can be expected to know everything. Therefore it makes sense to go for external profound knowledge.
Beside the specific know-how, the use of adequate methods and social skills are of great importance. Consultants are familiar with problems/changes in many companies of different subjects, at various levels of development and in different dimensions and thus can make their experience available to others.
It is not only a question of what to do but also of how to do things. External consultants have a wide range of methods to choose according to requirements. A good consultant gives accompany to his customer (he does not lead him). The main task of a consultant is to support his client in finding a satisfactory solution.
One of the major advantages of a neutral consultant is the critical external observation, which enables unbiased, non-directive decisions and can help to interrupt fixed, accustomed patterns and routine.
Moreover, external consultants have never been involved in personal conflicts of the past and will thus take decisions to the best of the project result in question.
Costs for permanent employees on the project will continue after process completion. Therefore the short-term investment for engaging external consultants should be equalized by medium to long-term savings and benefits from improvement.