It is a little world
- Cubed
In the 1960s, the designer Robert Propst worked with the Herman Miller company to produce “The Action Office”, a stylish system of open-plan office furniture that allowed workers to sit, stand, move around and configure the space as they wished.
Propst then watched in horror as his ideas were corrupted into cheap modular dividers, and then to cubicle farms or, as Propst described them, “barren, rathole places”. Managers had squeezed the style and the space out of the action office, but above all they had squeezed the ability of workers to make choices about the place where they spent much of their waking lives.
...It should be easy for the office to provide a vastly superior working environment to the home, because it is designed and equipped with work in mind. Few people can afford the space for a well-designed, well-specified home office. Many are reduced to perching on a bed or coffee table. And yet at home, nobody will rearrange the posters on your wall, and nobody will sneer about your “dog pictures, or whatever”. That seems trivial, but it is not.
The brick is one of those old technologies, like the wheel or paper, that seem to be basically unimprovable. ‘The shapes and sizes of bricks do not differ greatly wherever they are made,’ writes Edward Dobson in the fourteenth edition of his Rudimentary Treatise on the Manufacture of Bricks and Tiles. There’s a simple reason for the size: it has to fit in a human hand. As for the shape, building is much more straightforward if the width is half the length.
- We Don’t Really Know the Goal When We Start
- We Usually Don’t Know the Decision Tree – We Discover It as We Go
- The Nodes Are Really Not Design Decisions, but Tentative Complete Designs
- The Goodness Function Cannot be Evaluated Incrementally
- The Desiderata and Their Weightings Keep Changing
- The Constraints Keep Changing
We Don’t Really Know the Goal When We Start
The most serious model shortcoming is that the designer often has a vague, incompletely specified goal, or primary objective. In such cases, the hardest part of design is deciding what to design.
I came to realize that the most useful service I was performing for my client was helping him decide what he really wanted.
Today, we recognize that rapid prototyping is an essential tool for formulating precise requirements. Not only is the design process iterative; the design-goal-setting process is itself iterative. Knowing complete product requirements up front is a quite rare exception, not the norm. Therefore, goal iteration must be considered an inherent part of the design process.
The Goodness Function Cannot be Evaluated Incrementally
The Rational Model assumes that design involves a search of the decision tree, and that at every node, one can evaluate the goodness function of several downward branches. In fact, one cannot in general do this without exploring all the downward branches to all their leaves, which is possible in principle, but leads to a combinatorial explosion of alternatives in practice.
The Constraints Keep Changing
The explicit listing of known constraints in the design program helps here. The designer can periodically scan the list, asking, “Can this constraint now be removed because the world has changed? Can it be entirely circumvented by working outside the design space?”
Perhaps the most devastating critique of the Rational Model, although perhaps the hardest to prove, is that most experienced designers just don’t work that way.
“Conventional wisdom about problem-solving seems often to be contradicted by the behavior of expert designers. Empirical studies of design activity have frequently found ‘intuitive’ features of design ability to be the most effective and relevant to the intrinsic nature of design. Some aspects of design theory, however, have tried to develop counter-intuitive models and prescriptions for design behavior.” — Nigel Cross
Why all this fuss about the process model? Does the model we and others use to think about our design process really affect our designing itself? I believe it does. I believe our inadequate model and following it slavishly lead to fat, cumbersome, over-features products and also to schedule, budget, and performance disasters.
The Rational Model, in any of its forms, leads us to demand up-front statements of design requirements. It leads us to believe that such can be formulated. It leads us to make contracts with one another on the basis of enshrined ignorance. A more realistic process model would make design work more efficient, obviating many arguments with clients and much rework.
The Waterfall Model is wrong and harmful; we must outgrow it.