To a large extent, agile is about making tradeoffs. Product owners learn they can trade scope for schedule: get more later or less sooner. Agile projects need to strike a balance between no upfront thinking and too much upfront thinking, a subject I’ve written about before.
I want to write now about a tradeoff that isn’t talked about a lot in agile circles. And this is the tradeoff between schedule and cost. We’ve all heard the old story that nine women can’t make a baby in one month. But on software projects, it is possible (to some extent) to deliver a project faster by adding more people.
For example, suppose a project would take one person one year to do. Two people might be able to do it in six-and-a-half months. That’s one more total person-month to account for the overhead of communicating, for misunderstandings between the two, and so on. Adding a third, fourth or fifth person to the project will likely bring the calendar date in, but probably at the expense of more total person-months on the project.
Adding person-months to a project will presumably make the project more expensive to deliver. There is, then, a tradeoff to be made between schedule and cost. And most of the time, schedule wins. Companies always want things at the lowest cost they can—but not at the expense of schedule.
In an influential 1988 article in Harvard Business Review, George Stalk, Jr., declared that time was the next source of competitive advantage.
Originally Posted on Mountain Goat Software.