Software Project Estimation: What Control?

There are three primary project controls we can manipulate:

• Scope—controls the “what” of the solution

• Effort—represents the power we apply toward building the solution

• Duration—represents the time we have available for finishing the project

By adjusting each of these controls within the project envelope, we can affect the project’s progress and ultimately can drive the project toward desired objectives. There are other project aspects that can be recognized as distinct secondary controls. They have direct and indirect impact on the primary controls, and they are also very important in their own right for managing the less tangible outcomes of a project. These are the Environment, Software Quality, Metrics, and Value.

Environment, the well-being and collaborative capacity of people, can be treated as a secondary control. It almost directly converts to Effort— motivated people deliver more effectively. In this sense Environment can be considered part of the Effort primary control, and by improving the environment, we increase the available effort that can be expanded toward the project goal. 

Software Quality, the well-being and capacity for change in the code base, can also be treated as a secondary control. However, for most teams this is only a theoretical control since the quality that the team can attain is constant (and maximum) within the envelope of a single project. Lowering the quality is of course possible, but it cannot be considered a control since it doesn’t make sense. In any case, improving software quality, if it can be done sustainably within the project, also translates to Effort because once the team is working at an improved quality level, they get to expend less effort for achieving a comparable result.

Metrics, the health of the adopted development processes. Driving toward more controlled processes improves the predictability of events on the project and the likelihood of a forecast being close to the actual outcome. To the extent that an improved process can be proven to facilitate better productivity, we can consider it an effective project control. However, let’s not forget that individuals and interactions come before processes and tools. Enforcing rigid processes will backfire when creativity and thinking are the primary activities of people (which is the case on software development projects).

Value of the end product. Prioritizing functionality, so that we first complete the more valuable pieces, is a critically important derisking technique. Prioritization is a variation of the scope control. Occasionally people will discover valuable functionality that has not been previously recognized as an objective for the project. Pivoting for value represents product control, not project control. However, the value of the end result is so crucial for the project success that the project must accommodate changes to scope where this has been deemed the correct course of action. If the change in scope cannot be contained within the current project envelope, then the whole project needs to be reframed.