Why might developers use the resources found in the API developer portal?

Developers utilize the resources found in the API developer portal primarily to improve the integration of applications on Webex Calling. The API developer portal provides a wealth of documentation, tools, and resources that facilitate the development process, enabling developers to create applications that work seamlessly with Webex Calling services.

Through the API, developers can access various functionalities and features of Webex Calling, tapping into its capabilities to enhance their own applications. This can include functions like call handling, messaging, and user management, which are essential for creating robust, user-friendly applications. By leveraging the API documentation and sample code available in the portal, developers can ensure that their integrations are not only functional but also optimized for performance and user experience.

The other options do not directly relate to the primary functions of the API developer portal. Reviewing customer issue logs, monitoring network security incidents, and managing advertising strategies pertain to different areas of operations and do not align with the core purpose of the tools and resources offered in the portal, which focuses on application development and integration.