• Theories should be more central to research and practice. A good theory should
guide researchers in understanding relationships between concepts and generalizing
results. It should also guide practitioners when making design
tradeoffs for products. The power of theories to shape design is most apparent
in focused theories such as COMS or Fitts's Law; it is more difficult to
demonstrate for explanatory theories, whose main impact may be in educating
the next generation of designers or guiding research.
• Theories should lead rather than lag behind practice. Critics remark that too often a
theory is used to explain what has been produced by commercial product
designers. A robust theory should predict or at least guide practitioners in
designing new products. Effective theories should suggest novel products
and help refine existing ones.
Another direction for theoreticians is to predict subjective satisfaction or
emotional reactions of users. Researchers in media and advertising have recognized
the difficulty in predicting emotional reactions, so they complement theoretical
predictions with their intuitive judgments and extensive market testing.
Broader theories of small-group behavior, organizational dynamics, and sociology
are proving to be useful in understanding usage of collaborative interfaces
(Chapter 10). Similarly, the methods of anthropology or social psychology
may be helpful in understanding technology adoption and oyercoming barriers
to new technology that build resistance to change.