why do we go to university?

why do we go to university?
Different people have different points of view.But ,In my opinion,some university graduates do not have job in the world as well.Why?some students may regard universities as the most ideal places.They think they will certainly get jobs and higher pay after they graduate from a university .But often ,many of them feel disappointed at the university life and after graduation many of them can not find the jobs they are interested in and the pays are no higher than they have expected.
In fact,I know a university is a good place for those who are eager to learn more knowledge.It provides good chance for those who want to serve their motherland and make the people in his country lived a happy life in the future!
But, in that case.What shall I do?tell me.