From Wikipedia:
The Rational Model[edit]
The Rational Model was independently developed by Simon[14] and Pahl and Beitz.[15] It posits that:
designers attempt to optimize a design candidate for known constraints and objectives,
the design process is plan-driven,
the design process is understood in terms of a discrete sequence of stages.
The Rational Model is based on a rationalist philosophy[10] and underlies the Waterfall Model,[16] Systems Development Life Cycle[17] and much of the engineering design literature.[18] According to the rationalist philosophy, design is informed by research and knowledge in a predictable and controlled manner. Technical rationality is at the center of the process.[citation needed]
The Action-Centric Model[edit]
The Action-Centric Perspective is a label given to a collection of interrelated concepts, which are antithetical to The Rational Model.[12] It posits that:
designers use creativity and emotion to generate design candidates,
the design process is improvised,
no universal sequence of stages is apparent – analysis, design and implementation are contemporary and inextricably linked[12]
The Action-Centric Perspective is based on an empiricist philosophy and broadly consistent with the Agile approach[23] and amethodical development.[24] Substantial empirical evidence supports the veracity of this perspective in describing the actions of real designers.[21] Like the Rational Model, the Action-Centric model sees design as informed by research and knowledge. However, research and knowledge are brought into the design process through the judgment and common sense of designers – by designers "thinking on their feet" – more than through the predictable and controlled process stipulated by the Rational Model. Designers' context-dependent experience and professional judgment take center stage more than technical rationality.[citation needed]
Every project I do, I start out using the Rational Model. Then all hell breaks loose, and I switch to the Action Centric Model, and as I finalize the project, I go back to the Rational Model. What's the best model (if there is one) for the GRAPHIC design process?
