Sun, 03 Oct 2004
I don't think I have a firm grasp of XP's metaphor. Nevertheless, I am taken with the idea of using a guiding metaphor to encourage cohesive action. So what about a guiding metaphor for testing in Agile projects?
The picture on the right is my idea of conventional testing's dominant metaphor. The tester stands as a judge of the product. She acts by tossing darts at it. Those that stick find bugs. The revealing of bugs might cause good things to happen: bugs fixed, buggy releases delayed, a project manager who sleeps soundly at night because she's confident that the product is solid.
When talking to testers, two themes that often come up are independence and critical thinking. Critical thinking, I think, means healthy skepticism married to techniques for exercising it. Independence is needed to protect the tester from being infected with group think or being unduly pressured. A fair witness must be uninvolved to get at the truth.
There's no question in my mind that human projects often need people governed by this metaphor. But what about one type: Agile projects? Some say conventional testing exists, it's understood, and Agile projects need to import that knowledge.
I agree. We need the knowledge. But maybe not the metaphor and the attitudes that go with it. Independence and - to some extent - error-seeking are not a natural fit for Agile projects, which thrive on close teamwork and trust. Is there an alternate metaphor that we can build upon? One that works with trust and close teamwork, rather than independently of them? Can we minimize the need for the independent and critical judge?
I think so. Other fields have ways of harnessing critical thinking to trust and teamwork.
So, with those examples in mind, I offer this picture of an Agile team. They - programmers, testers, business experts - are in the business of protecting and nurturing the growing work until it's ready to face the world. (To symbolize that, I placed a book in the center, which is where herd animals like elephants, bison, and musk oxen place their young when danger threatens.)
Notice that the dinosaurs are all of the same species. Even though some of them might have special skills (perhaps one of them knows SAS, or was once a tester), they are more alike than they're different. They're all involved in making the weak parts strong and the strong parts stronger. (The latter is important: it's not enough to seek error; one must also preserve and amplify success, and spread understanding of how it was achieved throughout the team.)
P.S. Malcolm Gladwell wrote an interesting discussion of the virtues of group think.
Illustrations licensed from clipart.com.