ejbRemove() method is invoked when a client invokes a remove operation on the enterprise Bean's home interface or the EJB object's remote interface.
Not always true, as different beans have different lifecyles and are managed by the container.
For example, when a client invokes the remove() on a stateless session bean's remote interface, the container may do nothing.
ejbRemove() only gets called when the container decided to remove the object permanently. For CMP entity bean, the corresponding database row will also be removed.