Hiring a JSF developer is beneficial as they bring expertise in JavaServer Faces, a Java web application framework. They can create robust, efficient, and scalable web applications, ensuring a seamless user experience. With their knowledge in Java, they can integrate complex back-end logic with the user interface effectively. They are experienced in implementing enterprise-level security features, ensuring data protection. Furthermore, their ability to work with other Java-related technologies like JSP, Servlet, and EJB makes them versatile, enhancing the overall development process. They can help in maintaining code quality, which is crucial for long-term project sustainability.