Courses come in different varieties, and not all are amenable to online teaching and learning.
Let's segregate different types. We can start the first bucket of audio-friendly courses. These courses are narratable. Once well-crafted and with a great orator, the lectures can become a delight to anyone interested.
Some courses require equations and problem-solving. In the least, they require slides and other white-board type paraphernalia that the lecturer would need to present on. Students cannot be faulted for incomprehension if they cannot follow the slow process of mathematical constructs and numerical interplays.
More involved courses require visuals to illustrate what words can never adequately describe, like the simples molecules' spatial structures. Besides, some courses need laboratory sessions for the students to feel and smell, mix, and appreciate.
And, then there are courses that need tutors around to tailor the delivery for every individual. In addition to making students even understand what they have not understood, a tutor in tow becomes a must to help students do some homework to drive home the intricate points at every stage before moving on to the next.
Here is an audio course that requires all of the above. Importance of the content, information packed in, knowledge and oratorical skills of the professor cannot remotely compensate for the inadequacy of the single-dimensional delivery medium.
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