Power of oracle System user

Today i understand system db user  can change passwd of sys (supper user also ).

sqlplus system/One_1_Two_2T

SQL*Plus: Release 11.2.0.2.0 Production on Wed Sep 11 22:55:12 2013

Copyright (c) 1982, 2010, Oracle.  All rights reserved.

Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,
Data Mining and Real Application Testing options

SQL>
SQL> show user
USER is "SYSTEM"
SQL>
SQL> alter user sys identified by One_1_Two_2T;

User altered.

SQL>