Why 0 "Zero" in FNDCPASS?Lets Use 60 or 50.

I heard many times from people 0 Y is the mandatory in FNDCPASS/FNDLOAD and WFLOAD and i thought of writing this post to clear doubts  " ".

Default Priority for Concurrent Manager is 50.
Lowest Priority for Concurrent Manager is 99.
Highest Priority for Concurrent Manager is 0.

Lets do it practically
================
[applvision@apps ~]$ sqlplus apps/apps

SQL*Plus: Release 10.1.0.5.0 - Production on Fri Nov 8 02:25:17 2013

Copyright (c) 1982, 2005, Oracle.  All rights reserved.


Connected to:
Oracle Database 11g Enterprise Edition Release 11.1.0.7.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> exit
[applvision@apps ~]$ sqlplus system/manager

SQL*Plus: Release 10.1.0.5.0 - Production on Fri Nov 8 02:25:35 2013

Copyright (c) 1982, 2005, Oracle.  All rights reserved.


Connected to:
Oracle Database 11g Enterprise Edition Release 11.1.0.7.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> exit
[applvision@apps ~]$ FNDCPASS apps/apps 60 Y system/manager SYSTEM APPLSYS welcome123
Log filename : L407423.log


Report filename : O407423.out
[applvision@apps ~]$ cat L407423.log
+---------------------------------------------------------------------------+
Application Object Library: Version : 12.0.0

Copyright (c) 1979, 1999, Oracle Corporation. All rights reserved.

 module:
+---------------------------------------------------------------------------+

Current system time is 08-NOV-2013 02:27:13

+---------------------------------------------------------------------------+

Working...


+---------------------------------------------------------------------------+
Concurrent request completed successfully
Current system time is 08-NOV-2013 02:27:15

+---------------------------------------------------------------------------+
[applvision@apps ~]$ sqlplus apps/welcome123

SQL*Plus: Release 10.1.0.5.0 - Production on Fri Nov 8 02:27:32 2013

Copyright (c) 1982, 2005, Oracle.  All rights reserved.


Connected to:
Oracle Database 11g Enterprise Edition Release 11.1.0.7.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> show user
USER is "APPS"
SQL>

Note * :-

 From above practically hence it has been proved that "0" is the priority which can be change.

But it always best practice to use  "Oracle defaults"