Ensuring the that the organization is allocating its resources effectively and achieving the goals and objectives to which it is purposed not only keeps the organization effectively on course, but in addition the greater efficacy with which the organization is able to demonstrate its success, the greater its ability to attract donors and donations. Because of this, evaluation questions should be directed primarily at determining the degree to which an organization has achieved its goals and has proven itself to be cost effective in its achievements. This will present an attraction to donors as well as maintaining tight control over the operations of any given organization. The use of an outside consultant is not necessary for most evaluation purposes and would most likely result in an additional cash burden to any organization, and is therefore not recommended. Internal evaluations can be published in full, including the methodologies and raw data employed...

This serves the primary purpose of any non-profit organization by ensuring that it is truly meeting its goals and that it maintains the resources to continue working towards its goals in perpetuity. Marketing applications for evaluation results also exist. Donors should receive full evaluation reports upon request after organizational leadership has had an opportunity to develop plans in response to any evaluation's findings.
Reference

Fritz, J. (2010). Planned Giving. About.com. Accessed 11 November 2010.

http://nonprofit.about.com/od/pq/g/plangiv.htm