There are sever places user levels are set and the way they work are as follows.
Level 0 is unrestricted access and Level 5 is most restricted.
Each user is assigned a user level. Usually the operators are given user level 5 which is most restricted globally.
The actual global restrictions are set in "User Admin" - "User Levels"
The level users have does not inherently limit access to any tools or panels. That is controlled by layering the user levels in order of accessibility when designing the app.
When the user logs in, it determines what is available for that user.
Level 5 users can only use tools set to user level 5 access.
Level 4 users can access Level 5 and Level 4 tools.
Level 3 users can access Level 5, Level 4 and level 3 tools.
Level 2 users can access Level 5, though Level 2 tools.
Level 1 users can access Level 5, though Level 1 tools.
Level 0 users can access everything.
So, the panels and tools OK for everyone to use are set to Level 5 and the startup user is a Level 5.
Then panels and tools for operators are set to level 4
Panels for setup requiring technician would be set to level 3
Then to access the button or panel with more restriction, there would be a log on required for the user to enter their user name and password. The visibility and access can both be used to ether hide the tool from users not authorized to use it or just the access setting to keep them from using it when not at the correct security level.
Since the levels go backwards, the user level less than 5 makes the tool visible to level 4 through 0.
Hide if restricted works the same as the visibility example above. If it has a user level requirement of Level 3 and user is a level 5, the tool is not visible.
If "Hide if Restricted" is not checked, the tool is visible but not useable until a user with the correct or better user level logs on.
To restrict user access to certain panels, set the user level of the Go to Panel button to a lower numbered level.
I hope this makes it a little clearer. The backwards numbers where 0 is better than 5 is sometimes confusing.