Hi Juandre,
The 'SORT PRIORITY' property of a role defines its position in the Top level navigation in portal.
EX: Role A has sort priority as 1 and role B has sort priority as 2. Once you assign these two roles to a user, the user would see first Role A and then Role B.
We prefer sort priority of Home role for any portal to be 99 as the default value of sort priority is 100 for every role. Now in this case home role comes in the leftmost corner of the portal screen.
Please credit points if answer is helpful.
Thanks,
khyanaprabha