Oracle Database Discussions

if I create public database link its should be TRUE, What's the logic here ?

SQL>show parameter global_name;

NAME TYPE VALUE
global_names boolean FALSE

SQL>create public database link mydba connect to scott identified by tiger using 'ORCL';

Database link created.

SQL> select * from emp@mydba

select count(*) from emp@mydba;

COUNT(*)
14

Even i set global_name='FALSE' i can create public database link. then
why should i set global_name=*'TRUE'*