Most of the time, developers prefer to load Singleton objects because they consume memory efficiently rather than having several Prototype objects across the platform.

When it comes to the post-processing clean up, Spring will not have a hard time managing the resources used by Singleton since the entire application uses only one bean object during its request-response transactions. In the case of Prototype beans, the container must implement a post-processor that will clean up all the garbage and some bulk of resources consumed by the series of instantiations every fetch.