This is what the EJB spec says:
The choice between the local and the remote programming model is a design decision that the Bean Provider makes when developing the enterprise bean.
While it is possible to provide both a remote client view and a local client view for an enterprise bean, more typically only one or the other will be provided.
JSR220 Chapter 3
So when writing a bean think about who is the client, it’s very unlikely that a local client will need the same methods or even the same bean that a remote one.