To provide a summary of org's security health, an administrator should run a Health Check that compares org's settings against baseline settings defined by Salesforce Security Baseline Standard or industry standards such as CIS (Center for Internet Security) Benchmark Standard. Health Check generates an overall health score based on how org's settings match with baseline settings for various security categories such as Password Policies, Network Access, Session Settings etc. Health Check also provides recommendations for improving org's security health score by adjusting settings that do not match with baseline settings. Changing Org-Wide Default to private, turning on Event Monitoring, or downloading user login data will not provide a summary of org's security health. Reference: https://help.salesforce.com/s/articleView?id=sf.security_health_check.htm&type=5