Due to different models and systems of distance education, provided by different countries, their effectiveness should be evaluated by comparative evidence. It can also make a contribution to the effectiveness with which a program is implemented, because it encourages those involved to think more about what they are trying to achieve and how to evaluate the success.
Therefore, funding agencies usually require that the projects be evaluated to see their success rates as continued funding demands are based on some evidence of success. Accordingly, evaluation is also essential for development of ODL systems, and the findings can also suggest different areas which need to be developed. The integration of evaluation into the ODL systems can help identify some of the most intractable problems facing ODL systems. Finally, evaluation may be inevitable as a way of meeting requirements and self-assessment set by all interested bodies.