Delivering on Scope

Many writers on project management tell us that project management is about delivering the project on time and on budget, with a special emphasis that project management is about the 3 constraints of quality, cost, and time.

Turner writes that project management is about managing the scope and the organization, and that quality, cost, and time are just constraints.  Consider that the reason for the project is the work to be done (in order to reap the benefits of the project). 

Without the work, there is nothing.  Next, consider that the project organization is what does the work.  Without them, there is nothing.  The other three features: quality, cost, and time are not the purpose of the project. They are simply constraints. 

Handbook of Project-based Management