Asynchronous Learning is often associated with Distance Education Learning, Location Independent Learning, or Online Education, and Colleges. The core concepts around Asynchronous learning is that the teacher is in one location, and the students remain independently located often working at their own pace, maintaining their own goals, and not necessarily working at the same pace.
The teacher becomes more of a guide, versus a pure instructor. He becomes a storyteller versus a lecturer. It allows the student to become more of an apprentice and less of a slave to learning. This alternative form of learning has become hugely popular with the growth of the internet, and technology has given rise to many new forms of online colleges based around the core concepts of Asynchronous learning.
Asynchronous learning is student centric versus teacher centric. This is why it has become relatively successful, and is even being used in some alternative secondary institutes of learning.