INGOs do not conform to a limited range or organizational models. They are in fact characterized by a wide variety of forms. This reduces ability to understand them and consequently reduces their credibility. Furthermore the fact that the interests of INGOs do not always correspond to the priorities currently in fashion in the major intergovernmental agencies is considered to be an indication of their irrelevance.
It is important to seek innovation of organizational forms in order to develop more effectiveness. With regard to areas of interest, who is to say that a seemingly irrelevant INGO today should not be relevant tomorrow. (The best example is the existence of environmental INGOs several decades before the UN Stockholm conference on the human environment in 1972).