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Answer by Igor Markov, EECS Professor at Michigan
Good question.
Some universities count Coursera teaching toward regular teaching obligations. In other words, the university pays the teacher to teach on Coursera. Why do this? To officially be a part of Coursera.
One of my colleagues taught a course on Coursera out of interest and is not doing it again. But his course is now fully-automated and can be offered w/o his active participation (and has been).
An example mentioned by Daphne Koller (one of Coursera founders) on her recent visit to Michigan: a professor from a small college was normally getting twelve students in his/her course, but on Coursera, tens of thousands students signed up, and many completed the course -- great for personal fulfillment.
Keep in mind that some people like to teach and don't worry about money.
For example, at Stanford, you may find local professionals teaching for free -- it's a privilege. Coursera is essentially the same way, but less selective and with the bonus that your course will live forever.
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