Who builds effective networks remains an elusive question, particularly given mounting evidence that many people actually feel conflicted or ambivalent about the idea of instrumental networking. Here, we turn to an important piece of the puzzle that has been under-theorized: lay beliefs and attitudes that inhibit networking. Borrowing from the literature on implicit theories in motivational psychology, our theoretical model examines people's beliefs about three basic aspects of networking: the fixed versus malleable nature of social intelligence, social relations, and social capital. We explain how each lay belief affects people's attitudes toward both the utility and morality of networking, with consequences for their engagement in different forms of networking (i.e. searching for new ties, maintaining existing ties, and leveraging social capital). We also consider their downstream effects for the size, diversity, and cohesiveness of networks people build. Overall, by examining the role of domain-specific beliefs and attitudes that undermine people's motivation to network, our model departs from existing views of networking based on rationality, personality, and perception to shed new light on the motivational psychology of networking.