A design project should begin with some form of research that provides insight into human behavior and creates a context in which to begin the process of designing.
"Design plays a role that is distinct from, but complementary to the roles of science and of technological innovation in the advancement of knowledge ...
Designers are concerned with the socially, culturally, and spatially situated application of technologies to meet specific human needs. Successful design depends upon deep understanding of needs and their contexts, practical knowledge of the means available to respond, and strategies for creatively relating the two. It combines resourceful problem solving with ongoing critical reflection." -MIT Design Lab
Social science discplines like ethnography and anthropology are being adopted by designers to provide a basis for understanding (users).
Book: Design Research