Correct, in error, appropriate, or inappropriate? How are you going to know?

Today a colleague sent the following email:

I found this cute little diagram of the design process. Any comments?

A graphic dividing a system into 'correct' and 'in error' portions through phases of waterfall development

I limited my reply to:

Assumes that there is a “correct” functionality that can be completely specified in advance, and that any deviation from that complete specification is an “error”

I prefer to release small increments of functionality and get customer feedback; it’s hard to know if functionality is “appropriate” or “inappropriate” until customers are using it

This doesn’t mean you can put broken functionality in front of a customer. But it means that you’re not going to know whether the functionality you build really meets the customer’s need until they start using it.

I have no idea where my colleague got the diagram, so I can’t give appropriate credit. Sorry.

Published 17 October 2008, tags:


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