One of the main reasons why those from low caste (or those that are outcastes) are often unable to get out of poverty, is because they have largely remained poorly educated. The reason for this is that their schools are so bad that true learning does not occur.
Most villages have government schools that they can access but the teachers often don’t care and either don’t show up or just do a poor job of teaching. Learning becomes sub-standard and students are unable to pass exams which get them from primary to secondary education, or from secondary education to university. Some students that are very self motivated and are able to teach themselves by going through the text books, are able to progress, but most do not. Often the pressures of having to provide for their families overcome their ability to stay in school.
Most of those that go to university, were able to attend good private schools for primary and secondary education. These, obviously, cost money that the average low caste family cannot afford. So the system is perpetuated by keeping the high caste educated and in power.
This has been the way things are for thousands of years because Hinduism teaches that it is a crime for a low caste person to read. At times the crime of reading and learning was severely punished. Although this type of punishment no longer occurs, for the most part, the system mentioned above effectively perpetuates a poor education and continued poverty.