Shirky's chapter on Motives begins with an example of Josh Groban and his fans, who formed several charity organizations and continue to raise a lot of money for different charities in Groban's name each year. This section is followed up with an example of an experiment by Deci, involving a Soma cube to examine the difference between intrinsic and extrinsic motivations.
The juxtaposition of these two examples is intriguing. As per my understanding, intrinsic motives come from people's interests. If they do something purely because they are interested in doing it, or have some sort of love or passion for the activity they are pursuing. On the other hand, someone is extrinsically motivated if there are outside influences motivating them to complete a task.