This article is one in a series about the problem of identifying and clarifying client requirements. This episode looks at why clients often appear to change their minds dramatically, and how you can handle that problem within your development process.
Readers who like the extended metaphor of the client requiring an image of an elephant might like to know that we’re continuing with it in this article. Readers for whom the novelty of that metaphor has worn thin might like to know that we won’t be using it much.
So, why do clients appear to change their minds radically? It’s often because of a very simple reason that is easy to handle.
This article is part of a series about identifying and clarifying client requirements. Handling client requirements isn’t always easy. However, that isn’t the same as “impossible” or “not worth trying”. The previous article covered three ways of getting it wrong, and various ways of getting it right; this article follows on from that point.
As a running theme through this series, we’re imagining that you’re dealing with a client who has asked you to produce an image of an elephant. Here’s another inadvisable solution.
Bad solution 4: My design is in a witty dialogue with its environment
Client’s response: Very funny, go get a job at the circus.
Often, a small example can give key insights into bigger, deeper questions. The saga of our cat flap is one of those cases. It’s an apparently trivial problem that leads swiftly into important, difficult questions like how to tackle design decisions, and how to identify design options that you might easily have overlooked, and how to spot design problems in the first place.
That’s how we ended up as one of the few the families in England to have a raccoon flap in their back door, rather than a cat flap. It’s an excellent example of design rationale – the reasoning behind a particular design decision. Like most problems involving design solutions to client requirements, it takes us into the difficult territory where human beings have trouble establishing just what they want and why they want it, and where designers are trying to find a way of tackling the problem that’s systematic but that can also capture the often messy requirements and constraints affecting a particular problem.
I’ll tell the cat flap story first, and then work through the insights that it gives about design rationale.
Graph theory is an extremely powerful approach that is based on a handful of elegantly simple concepts. It was invented by Euler in the 1740s, and is a central part of modern mathematics and technology. Among other things, it plays a key role in handling traffic on the Internet.
It’s invaluable for representing knowledge, because it combines flexibility with formalism. In particular, it’s useful for representing different facets and viewpoints; for representing hierarchies of goals and values; for representing successive layers of explanations; and for formal taxonomies. Continue reading →