Some Standard Center Tabs can be removed for Custom and Standard Roles.
If the "Set Up Custom Tab" link can be seen under Center Tab Overview, then this Tab can be removed for a Role.
1. Navigate to Setup > Users/Roles > Manage Roles.
2. Customize the Role and note the Center Type.
3. In Permissions tab > Setup subtab > set Custom Center Tabs = Full.
4. Click Save.
5. Switch to the newly created Custom Role.
6. Navigate to the Center Tab that is to be removed > Select Overview.
7. Click Set Up Custom Tab link in the upper-right of the main section of the page.
8. Edit the custom tab > Name = (should not be changed or edited in any way).
9. Click Audience tab > Roles checkbox > Select All = False.
10. Click Save.
Results: The Center Tab will now be removed for the Role with the same Center Type.