Responding to Change over Following a Plan
The ability to respond to change often determines the success or failure of a software project. When
we build plans, we need to make sure that they are flexible and ready to adapt to changes in the
business and technology.
The course of a software project cannot be planned very far into the future. First, the business
environment is likely to change, causing the requirements to shift. Second, once they see the system
start to function, customers are likely to alter the requirements. Finally, even if we know what the
requirements are and are sure that they won't change, we are not very good at estimating how long
it will take to develop them.
It is tempting for novice managers to create and tape to the wall a nice PERT or Gantt chart of the
whole project. They may feel that this chart gives them control over the project. They can track the
individual tasks and cross them off the chart as they are completed. They can compare the actual
dates with the planned dates on the chart and react to any discrepancies.
But what really happens is that the structure of the chart degrades. As the team gains knowledge
about the system and as the customer gains knowledge about the team's needs, certain tasks on the
chart will become unnecessary. Other tasks will be discovered and will need to be added. In short,
the plan will undergo changes in shape, not only in dates.
A better planning strategy is to make detailed plans for the next week, rough plans for the next 3
months, and extremely crude plans beyond that. We should know the individual tasks we will be
working on for the next week. We should roughly know the requirements we will be working on for
the next 3 months. And we should have only a vague idea what the system will do after a year.
This decreasing resolution of the plan means that we are investing in a detailed plan only for those
tasks that are immediate. Once the detailed plan is made, it is difficult to change, since the team will
have a lot of momentum and commitment. But since that plan governs only a week's worth of time,