Datasheet

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CHAPTER 1 SHIPPING SOFTWARE
While heavy documentation has advantages in terms of oversight and traceability, there are
major problems with it. First, it assumes that people will read the documents. This is rarely the
case, as documents frequently exceed hundreds of pages. Second, it assumes that the reader can
understand the documents. This is also rarely the case. Business users don ’ t speak or write in terms
of “ requirements, ” yet they are expected to approve a document written in that language. They
generally approve a document based on their trust of the people writing it, but this allows errors and
omission to easily slip past review. Finally, the more the team focuses on documentation, the less it
focuses on the actual task at hand — building great software.
COMPARING METHODOLOGIES
The following sections compare the three project management techniques according to primary
characteristics. The intent is to help you understand the similarities and differences, so you can use
your experience with Waterfall or MSF to gain insight into Scrum.
Product Defi nition
How, when, and by whom is a product defi ned? How are the user needs and expectations
captured? How are requirements communicated to the technical team? How does the technical team
communicate with users? The three project management methodologies address product defi nition
as follows:
Waterfall — Product requirements are extensively documented during the fi rst phase
of a project. They are generally expressed in a technical grammar rather than natural
language, although they are describing business goals rather than technology. At the end
of the requirements defi nition phase, the capabilities of the system are fully specifi ed. The
requirements document can be used for tendering proposals from competing vendors to do
the implementation.
MSF — The product defi nition begins with a vision/scope document, which is a narrative
description of the high - level goals and motivations of the project. This document is used to
build a functional specifi cation that fully describes the product. The functional specifi cation
can be used for tendering proposals from competing vendors to do the implementation.
Scrum — The product defi nition is captured as user stories and expressed in natural
language, in the form
< someone > wants to do < something > because < reason > . User
stories are decomposed and expanded closer to implementation. The feature set for the
system is dynamic and changes throughout the project life cycle.
Adaptability
How does each methodology work with changing requirements? Does the methodology favor a stable
or changing landscape? The three project management methodologies address adaptability as follows:
Waterfall — Requirements are locked down early in the project life cycle. Changes
introduced later in the project can have a large ripple effect on time and cost. Change orders
are used to track and schedule cost and features. A big design phase up front can produce a
predictable cost and schedule.
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