The primary advantage of utilizing microservices architecture is its ability to improve scalability and maintainability of applications. In this design, applications are broken down into smaller, independent services that can be developed, deployed, and scaled individually. This allows teams to use diverse technologies and languages tailored to specific tasks, leading to faster development cycles and easier updates. Furthermore, if one service fails, it does not affect the entire application, enhancing overall system resilience and providing flexibility to adapt to changing business needs.