Loading ...
Sorry, an error occurred while loading the content.

Re: [XP] XP and stories introduced at a late stage of the project

Expand Messages
  • J. B. Rainsberger
    ... In my opinion, no. It does identify a problem in how many people think about XP, though: we don t claim for a moment that you don t have to /think/ up
    Message 1 of 16 , Oct 29, 2006
    • 0 Attachment
      sja085 wrote:

      > My question is; Doesn't this identify a problem in XP model, where
      > it seems that all requirements need to be gathered before the
      > project is started!?

      In my opinion, no. It does identify a problem in how many people think
      about XP, though: we don't claim for a moment that you don't have to
      /think/ up front. We do claim, however, that if the design is kept
      simple, then we minimize the cost of making this decision late in the
      project.

      Let me be clear on my assumptions:

      1. The client told us about the Localization story as soon as he
      discovered it. That means at the earliest possible planning meeting, or
      sooner.

      2. We have kept the design small and simple while keeping the tests passing.

      If these assumptions are correct, then we have done the best we can. Why?

      A. When we saw Story 550, we estimated it as big, explained why, and
      explained that the later we wait to do it, the more it will cost.

      B. The story /only/ (!!) takes 3 weeks because the design is simple. If
      we had included Localization from the beginning /and never needed it/,
      we might have spent 3 week of overhead maintaining that extra code, anyway.

      C. Even if we would have only spent 1 week of overhead maintaining
      unnecessary code, it tends to be true that some unnecessary code breeds
      more unnecessary code. (This point is weak, but I believe it to be true.)

      So if my assumptions are incorrect, and your customer /hid/ the
      Localization story from you, then he incurred unnecessary risk, and that
      is /not/ a practice in XP. It might simply be a result of a lack of
      experience, as I've seen this happen on teams that practice any method.

      Good luck.
      --
      J. B. (Joe) Rainsberger :: http://www.jbrains.ca
      Your guide to software craftsmanship
      JUnit Recipes: Practical Methods for Programmer Testing
      2005 Gordon Pask Award for contribution Agile Software Practice
    Your message has been successfully submitted and would be delivered to recipients shortly.