Effective governance over IT infrastructure is indicated by the ability to deliver continuous, reliable performance12. This is because good governance ensures that IT investments support business objectives and produce measurable results towards achieving their strategies2. It involves implementing management and internal controls, strengthening security, financial controls, risk mitigation, and inspection and compliance obligations3. While security awareness programs, the number of servers, and the number of security incidents can be aspects of IT governance, they are not the best indicators of its effectiveness.
References:
The Value of IT Governance - ISACA
What is IT governance? A formal way to align IT & business strategy | CIO Robust Governance - KPMG Global

The effectiveness of an organization's security awareness program can be measured by capturing data on changes in the way people react to threats, such as the ability to recognize and avoid social engineering attacks1. An increase in the number of phishing emails reported by employees indicates that they are more aware of the signs and risks of phishing, and are more likely to take appropriate actions to prevent or mitigate the impact of such attacks23.
References
1: The Importance Of Measuring Security Awareness 2: Measuring the effectiveness of your security awareness program 3: How effective is security awareness training?

The most beneficial stage of the system development life cycle (SDLC) to consider data privacy principles is D: Requirements definition. This is because data privacy principles should be integrated into the design and development of customer-facing IT applications from the very beginning, not as an afterthought or a retrofit1. By considering data privacy principles in the requirements definition stage, the developers can identify the personal data that will be collected, processed, stored, and shared by the application, and ensure that they comply with the relevant laws and regulations, such as the General Data Protection Regulation (GDPR)2. They can also apply the principles of data minimization, purpose limitation, transparency, consent, and security to protect the privacy rights and interests of the customers3.