A DESCRIPTION OF THE PROBLEM :
I hope I found the correct category:
https://docs.oracle.com/en/java/javase/17/docs/api/java.base/java/util/concurrent/ExecutorService.html#shutdown()

The docs on shutdown() both states:
 - Initiates an orderly shutdown in which previously submitted tasks are executed.
 - This method does not wait for previously submitted tasks to complete execution.
To me, this is a contradiction.

FREQUENCY : always