Dan Pink points out that in our career path we make decisions for fundamental and instrumental reasons. An instrumental reason is made because you think it is going to lead to something else, regardless of whether you enjoy it or not.
You can also do something that is because of a fundamental reason. A fundamental reason is done because YOU think it is inherently valuable regardless of what it may or may not lead to.
(Reference: The Adventures of Johnny Bunko by Dan Pink)
I have an example in my own path in each category:
Instrumental reason example: Early on in my financial services career, someone encouraged me to go off an get my MBA in Accounting. The idea is that it would open doors and provide flexibility. I did not really enjoy accounting. I liked the concepts and felt like I was sharpening my sword, but I am not accountant material. I had in the back of my mind that it would lead to something else.
Fundamental Reason: I am faced with this today. Pursuing this idea of helping folks move from A to B in their career process is something I feel is inherently valuable. I really do not know what it will lead to.