According to the PMBOKĀ® Guide, tailoring is necessary because every project is unique. The project manager must customize the processes within the Project Scope Management knowledge area to fit the specific needs of the project.
The PMI standards specifically list the following tailoring considerations for Project Scope Management:
Knowledge and Content Management: Does the organization have formal or informal knowledge management systems?
Continuous Improvement: Does the organization have a formal process for continuous improvement (such as Kaizen or Six Sigma), and how does that influence the definition and management of scope?
Stability of Requirements: Are the requirements stable, or do they evolve (as in Agile environments)?
Governance: Does the organization have formal policies and procedures for scope oversight?
Analysis of other options:
Life cycle approach: This is a tailoring consideration for Project Integration Management or the project as a whole, rather than specifically listed under Scope Management tailoring.
Validation and control: These are core processes (Validate Scope and Control Scope) within the knowledge area, not the high-level factors used to tailor those processes.
Project complexity: While project complexity influences tailoring for many knowledge areas, it is a broad environmental factor. In the context of Scope Management specifically, Continuous improvement is explicitly cited in the PMBOKĀ® Guide as a specific tailoring dimension regarding how requirements and scope are refined over time.
By considering Continuous improvement, the project manager determines how frequently the scope should be reviewed and updated to ensure it remains aligned with business value.