Specification: the importance of purpose

If I were to ask you what you could do with a stick like as not you'd quickly come up with half a dozen entirely practicable ideas. You could use it to prod cans off supermarket shelves or prop up a flower stem, You could poke a wasps' nest or hit a golf ball across the lawn. You could stir concrete or poke holes in doughnuts with it. And so on until bedtime.

But what if I asked you what a stick could do? You'd probably need to think a bit about that. Especially if I asked what a stick could do that wasn't really what you could do with a stick. It could stay where it was or it could rot or, if it were fresh off the tree, it might take root and grow. There aren't many other options as spring immediately to mind.

Like any technology, the usefulness or not of the stick is dependent on the purpose to which it is actually applied. This is why whenever we're looking at any new equipment or application the "What would you want to do with it?" question is infinitely more important than "What does it do?" It may be capable of doing very many splendid things but until somebody actually puts it to work these are only a potential usefulness. And very often the use a technology is put to isn't the one intended by the person who built it (screwdrivers weren't designed for levering the lids off tins of paint, they just happen to be very useful for doing so).

When you're building a specification or statement of user requirements you need to be mindful of the difference between describing what something will be and describing what something will do. Specifications too often describe — and prescribe — processes without describing their preferred outcomes. Which is perverse because if the object isn't to specify a physical object or deploy some sort of brand you want as much freedom of interpretation as possible. In design thinking terms you're defining the problem not building the prototype.

The purpose of specification is to define the problem to be solved. If you use the specification to define the prototype then you could be missing out on better potential solutions. Like Henry Ford might or might not have said: "If I had asked people what they wanted, they would have said faster horses."