Hiring a JPA (Hibernate) developer can streamline your application's interaction with databases. These developers are skilled in mapping Java objects to relational database tables, which simplifies data persistence. They can write complex queries and perform CRUD operations efficiently, ensuring smooth data transactions. Their expertise in handling database-related issues and implementing Hibernate's advanced features can enhance your application's performance. Moreover, they can help in optimizing your application through caching, lazy loading, and transaction management strategies. Their skills can be invaluable for creating robust, efficient, and scalable applications.