Student success in online courses may not be anything more than their sheer motivation to finish school. Online education is a valid option for those who desire to achieve their goals without having to stop life. Those who would most likely succeed in a traditional model may just also be most likely to succeed in an online model. A good student is simply a good student regardless of modality.
According to a study looking at successful students in qualitative and quantitative courses found that the biggest factor in success was previous GPA (Tanke & Logan, 2012). Demographics didn't have an impact on success. The successful student in ground-based courses was just as likely to be successful in an online course.
Despite life's circumstances, something deep pushes some people to keep learning no mater what difficulties they face. They may have competing responsibilities and engage in online education because it offers them access that other schools don't offer.
The motivated student will succeed wherever and in whatever manner they can. Changing the modality only changes the market reach but doesn't change the desire to learn. Whole groups of highly intelligent people would be left behind without online education.
If online success is predicted primarily by previous success than the quality of student can be solicited based on skill level. For example a more elite school would be selective to high performing individuals while another school might be accepting of less qualified individuals. their performance is expected to match previous performance in high school, training, life and education.
Tanke, M. & Logan, T. (2012). The influence of demographic factors on student success in online vs. fact-to-face instruction in hospitality education. Review of Higher Education & Self-Learning, 5 (16).