In Spring Framework, some bean names are predefined or convention-based, meaning they are expected to have specific names for certain functionalities to work correctly. The CommonsMultipartResolver bean is one such bean where the name is convention-based, and it is expected to be named "multipartResolver" by default. Changing it to "multiPartResolver" or any other name may cause issues because Spring might not be able to automatically recognize it as the bean responsible for handling file uploads.