In the case of Configuration, developers have to create the build processes manually and they have to specify each and every configuration in detail. But, Maven uses convention where the developers need not create the build processes manually.
Also, for convention, users do not need to specify the configuration in detail. Once a developer creates a project in Maven then Maven will automatically create a structure. Developers just have to place the files appropriately. There is no need to specify any configuration details in pom.xml file.