Confirmation of SQL statement disappeared
If the feedback on SQL*Plus is set to off then you don't get the confirmation messages. 

SQL&gt; set feedback off
SQL&gt; create user c##u1 identified by user1;


set feedback on.

SQL&gt; set feedback on
SQL&gt; drop user c##u1;

User dropped.

SQL&gt; create user c##u1 identified by user1;

User created.


Documentation: SET FEEDBACK