Self study is an individual effort to learn by references/experimentation or a prescribed course.
1.You have privacy& independence with no fear of criticism.
2.You have your own scheduled time.
3.You can refer to other sources.
1. Understanding the study many be difficult without a mentor.
2.No certainty if you are studying the right thing.
3.A fixed schedule.
4.The quality may be poor
5.Waste of time in learning.