Without Spring Boot

If Spring Boot is not used, developing stand-alone, production-grade applications using Spring becomes more complex and time-consuming. Without the opinionated view and automatic configuration provided by Spring Boot, developers would need to manually configure Spring and third-party libraries, which can be tedious and error-prone. Additionally, Spring Boot's production-ready features, such as metrics, health checks, and externalized configuration, would not be available out of the box. This could result in increased effort and cost to build and maintain applications, as these features would need to be implemented manually.