The author reflects on their evolution as a Product Manager, initially believing that integrating SaaS products required visible UI elements like buttons but later realizing the critical role of APIs, particularly OpenAPI, in this process. They describe OpenAPI as the backbone of integration, acting as a static, contractual definition of how APIs function and can be utilized, rather than actively executing actions. The author highlights the importance of having a reliable "source of truth," drawing a parallel to Git repositories, where the latest version of an API definition can be accessed. Phil Sturgeon's guide on OpenAPI is praised for distilling a decade of experience and offering best practices and tools for managing an API lifecycle. The text emphasizes the open-source nature of this content, encouraging community feedback and contributions to enhance its development.