When you're focusing on your own skills you're polishing an aging vehicle for value delivery, which is mostly only good when someone else glues you with other people. When you're polishing a social network you're engaging in a more amorphous activity with respect to value, but you're also investing in something beyond you, a kind of social coherency which will likely outlast your death.
I think thats really true from the perspective of a fairly experienced person but I also think it takes a level of skill to build social currency. Building a network is 10x easier when you have done something noteworthy compared to just pure networking off your personality or whatever.
