When it comes to managing your project you should have a well-defined scope and a detailed plan. In project management there are actually two types of scope: product scope and project scope. So what is the difference? Well, lets start with the product scope.
The product scope is the end result of your project. It describes the final outcome which will exist after your project is complete, be it an application or a service. Product scope is what your project sponsors will focus on; its what they envision for you to create. During the requirements gathering phase of your project, your sponsor should be able to clearly outline your product scope as they describe their expectations of how the application or the service will work.
The project scope, on the other hand, will outline the required steps which are needed to successfully achieve the desired product scope. This includes all required work in order to complete the project deliverable and usually consists of four parameters: budget, timeline, quality and objectives. Product scope and project scope support one another; in order to have a clear understanding of your project scope, you need to have a well-defined product scope.
For a project manager, the requirements gathering is a key phase in their project management. You should not begin your project until you have a clear understanding of the requirements for acceptance (product scope), as this will help you plan the four parameters of your project scope. If either the product or project scope are wrong, you and your team end up wasting time and money, not to mention being forced to redo work in the future. Obtaining a clear product scope, which in result will define the project scope, is vital for the success of your project.