3.6. Java EE components

I don't understand this text:

"The instance used by the container to service an invocation of a Java EE component will not be the same instance obtained when using @Inject, instantiated by the container to invoke a producer method, observer method or disposer method, or instantiated by the container to access the value of a producer field."

More specifically, I am trying to understand how we can use CDI to put a scope on EntityManager whose life cycle is rather undefined by JPA. I see that the specification use an example of a @Disposes method to close a container-managed entity manager which throw IllegalStateException in the disposer . Anyways, trying to solve this puzzle has led me to the paragraph quoted previously, of which I understand nothing to be honest.

My research about the "CDI managed container-managed entity manager" continues. As of now, the example is flawed and a container-managed entity manager remains open after the disposer method. Anyways, I might open up a separate ticket for that.