“The process of human-centered design relies heavily on modeling the behavior of target users in an effort to understand what people might, would, or should do with a new design. A model is a representation of a real thing, and a model of user behavior is a representation of the actions a person might perform and emotions a person might feel over time.” (Kolko, 2011)
It is difficult to predict human behavior and it’s even more difficult to tap into the internal processes of the human mind. The Sci-fi version of this idea is that there is no way to prove that other people have a conscious mind and think the same way as you do and it is logically possible that everyone else in the world is an eloquently constructed robot who can act conscious but aren’t really conscious the way you are (Dennet, 2013).
How then are we supposed to design for other people? The simple answer is, by observing them thoroughly; by expecting them to act rationally and by asking them questions. Put yourself in their shoes, if possible. Create stories including actors, goals, tasks, benefits and supporting functions (Kolko, 2011). Act them out with a prototype if possible, with paper and pen if not. It’s worth your time to do all this.
References
Thinking about People in Kolko, J. (2011). Thoughts on Interaction Design (2nd ed.) Burlington, MA: Morgan Kaufmann (pg. 20 – 39)
Dennett, D. C. (2013). Intuition pumps and other tools for thinking. WW Norton & Company. (pp. 288 – 295)