http://www.perlmonks.org?node_id=63083


in reply to (redmist) Re: Benefits of the Specification
in thread Benefits of the Specification

The really Bad Thing about not thinking about the application, is that every time you add something, something else will inevitably break.

Until recently, this has been predominant view: If you don't Plan Ahead, things will break later.

Extreme Programming offers a novel counter proposal: If you only think one step ahead, and at the end of each step you have a well-tested, well-factored system, then the chances of your breaking something on the next, not-yet-thought-of step are reduced to near zero. Well-factored implies good structure, with things done "once and only once". Then means that many decisions are well localized. A well localized decision is much easier to safely change or replace than once that's becomes spread out over time.