Datasheet

One place where Scrum is different from traditional software project management methodologies
(such as the Waterfall method) is with respect to predictability. Waterfall assumes that you can
predict how long tasks will take. You allocate people and time to tasks and then schedule them
accordingly. Scrum assumes the opposite. You cannot accurately predict how long something will
take unless you ’ ve done it with the same resources (technology and people) before.
If you cannot predict how long a single task will take, how can you predict how long a whole series
of tasks will take? Using Scrum, you accept the fact that you can ’ t. Rather than predict the product
schedule, you predict smaller units of work that can be completed within a sprint. At the end of
each sprint, features are complete and can be included in a potentially shippable product. This way,
you predict features by time rather than predicting time by features, which is essentially a time - box
approach.
A sprint is the smallest cycle time within Scrum. Chapter 9 focuses on running sprints. Sprints can
be as long as a month or two and as short as a day or two. The ScrumMaster decides the duration
before the sprint begins. Each sprint starts with a sprint planning meeting, during which the team
looks at the product backlog and decides which features to build during the sprint. The team
members use their experience in the previous sprint(s) to predict how much they can accomplish
in the next sprint. This is signifi cantly different from the Waterfall method, which involves
predicting the release and features up front and allocating time and people to the tasks.
FIGURE 1 - 1: Waterfall and Scrum planning.
The Waterfall method of project management is the method most commonly
used to run software projects. When using the Waterfall method, you schedule
tasks sequentially, completing one phase of activity before beginning the next.
Later in the chapter, in the “ Approaches to Project Management ” section, we ’ ll
look more closely at the Waterfall method and compare it with Scrum.
What Do You Need to Ship Software?
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