Can duties harm us? Can being obligated to do something of itself make a person worse off, at least sometimes?
Duties and obligations – or the conditions which trigger preexisting duties and obligations – are often greeted with resignation by those who have them just as if they were bad news, at any rate. Even if Yann quite likes his job teaching philosophy and understands that he may be assigned administrative duties as a condition of employment, he might also be quite disappointed when he remembers all the graduate student applications he must read tomorrow, just when he was hoping to spend a day on research. He just found out that things are a little bit worse for him than he thought. Shante might hate the very idea of a monster truck rally but go to one for the sake of a friend who wants her to have a “cultural experience.” What motivates her is a sense of duty to the friend, not any desire to see cars smashed; she would have preferred never to have been invited, because then she wouldn’t have to go.
Of course a good friendship is usually not a burden, and having obligations and filling them can indeed be part of what is good about a friendship. Such duties do not even seem pro tanto bad for those who have them. Joseph Raz puts it best:
Some activities and relationships which cannot be specified except by reference to duties are intrinsically good. Friendship is such a case in which the two properties coincide. Friendships ought to be cultivated for their own sake. They are intrinsically valuable. At the same time the relations between friends, the relationship which constitutes friendship, cannot be specified except by reference to the duties of friendship. When this is the case the justifying good is internally related to the duty. The duty is (an element of) the good itself. 
Let’s suppose it’s the duties themselves which can be said to affect our well-being in the cases above. If that’s so, then what makes their effect positive or negative? When do duties enhance our well-being, and when do they detract from it? Here’s one answer:
Obvious Account (OA): New duties benefit us to the extent that they increase our expected future well-being and harm us to the extent that they decrease it.
In this post, I want to suggest that OA cannot account for a way in which a duty can itself be a harm.