在创建新的systemd服务时，何时需要将RemainAfterExit选项设置为true？

I am trying to write a few services. Some of them have 'type' option set to oneshot. But i am still confused when the option 'RemainAfterExit' needs to be set true. (not just that service needs to be active even after exiting).I am trying to write a few services. Some of th