Chapter 5: The On-site Customer

Overview

Schedule Is the Customer s Problem (The Man with Kaleidoscope Eyes)

(Sing to the tune of Lucy in the Sky with Diamonds by The Beatles)

Picture a waterfall run through a blender
With each iteration so tiny in size
Somebody tells you that change is not costly
The man with kaleidoscope eyes

Endless refactoring day after day
While deadlines are slipping away
Suddenly there comes a saying that makes it okay

Schedule is the customer s problem
Schedule is the customer s problem
Schedule is the customer s problem

Ahhhhhhhhhhhhhhhh

GROUCHO  

Once you accept that scope is variable then suddenly the project is no longer about getting ˜done . Rather its [sic] about developing at a certain velocity. And once you establish a velocity then the schedule becomes the customer s problem. ^[1]
”Robert C. Martin

Back in Chapter 1, we discussed briefly how the XP customer role has evolved from a single actual on-site customer to a large team of customers. In this chapter, we look at both of these options (or, as we call them, the Old and New Testaments). We also question the sanity of replacing specifications with colocated customer teams that must speak with a single voice if the project is to avoid doom.

Currently it looks as if the on-site customer role has become a pickandmix part of XP ”just dial up how many customers you want and hope that the rest of XP fits. At this time XP has little or no guidance regarding how its other practices should be modified to fit each of the customer models.

But first, we examine how XP offloads responsibility for many of the not fun parts of software development from the programmers to the customer(s).

^[1] Robert C. Martin posting to OTUG ( http://www.rational.com), subject: Scope Creep, October 11, 2000.