Society vs Person Commitment
Fleetingsociety vs person commitment
There are stuffs that I have to do because I explicitly committed to someone. And there are stuff that I have to do because I have some implicit reason to do them.
I realize that the diffusion of responsibility make the latter harder to commit to. If at some point I realize that really want to have it done, I should wonder whether not doing it will disturb someone and explicitly commit against this person.