According to the NIST Cybersecurity Framework, mission drivers are a primary consideration when creating an action plan to address gaps identified in CSF Step 6, as they help to align the cybersecurity program with the organization's objectives, priorities, and risk appetite. Mission drivers also help to determine the resources needed and the cost-benefit analysis of the proposed solutions12.
References7 Steps to Implement & Improve Cybersecurity with NISTCybersecurity Framework v1.1 - CSF Tools - Identity Digital, page 7.

The most important reason to compare framework profiles is to identify gaps between the current and target state of cybersecurity activities and outcomes, and to prioritize the actions needed to address them12.
Framework profiles are the alignment of the functions, categories, and subcategories of the NIST Cybersecurity Framework with the business requirements, risk tolerance, and resources of the organization3.
By comparing the current profile (what is being achieved) and the target profile (what is needed), an organization can assess its cybersecurity posture and develop a roadmap for improvement4.
References: 1: Cybersecurity Framework Components | NIST 2: Implementing the NIST Cybersecurity Framework Using COBIT 2019 | ISACA 3: Examples of Framework Profiles | NIST 4: Connecting COBIT
2019 to the NIST Cybersecurity Framework - ISACA

This CSF step corresponds to the COBIT objective of knowledge and understanding of enterprise goals, because it involves identifying the business drivers, mission, objectives, and risk appetite of the organization, as well as the scope and boundaries of the cybersecurity program12. This step helps to ensure that the cybersecurity activities and outcomes are aligned with the enterprise goals and strategy34.
References: 1: Cybersecurity Framework Components | NIST 2: Implementing the NIST Cybersecurity Framework Using COBIT 2019 | ISACA 3: COBIT 2019 Design and Implementation COBIT Implementation
4: COBIT 2019 Foundation | Skillsoft Global Knowledge

One of the most likely causes of an organization's NIST CSF implementation failure is that the potential benefits of proposed improvements are not considered, which means that the organization does not conduct a cost-benefit analysis of the solutions to address the gaps between the current and target profiles. This can result in a lack of justification, prioritization, and alignment of the implementation plan with the organization's mission drivers, risk appetite, and resource constraints12.
References7 Steps to Implement & Improve Cybersecurity with NIST3 Security Issues Overlooked By the NIST Framework

Defining business cases is a primary input into Steps 2 and 3: Orient and Create a Current Profile, because it involves identifying the business drivers, mission, objectives, and risk appetite of the organization, as well as the scope and boundaries of the cybersecurity program12. A business case is a document that provides the rationale and justification for initiating a cybersecurity project or program, and describes the expected benefits, costs, risks, and alternatives34.
References: 1: Cybersecurity Framework Components | NIST 2: Implementing the NIST Cybersecurity Framework Using COBIT 2019 | ISACA 3: Business Case Development - ISACA 4: How to Write a Business Case for Cybersecurity Projects | Infosec