Something that can often catch new users out is the structural steel components in the default Revit library.
There are so many visibility options in Revit, but when it comes to families, aside from the typical project visibility issues, often the settings in the family itself are overlooked.
If we take the above example using the structural steel components, most of these families have been built with the course detail tick box turned off under 'family element visibility settings'.
The families will instead display thick lines at this detail level. If you have ever seen structural engineering sections, you will notice this display.
Personally, for my Architectural drawings, I have never had a need for either of these settings but I know structural engineers use them all the time. I have simply made a copy of this library content and modified each of the families for use in our projects.
Tip! Something else to be mindful of with the structural families, particularly the SHS or RHS members. These components have 2 extrusions within the family.
You will notice one extrusion with filleted edges (this is on fine detail level) and another extrusion in the same place with a hard edge, (this is on the medium detail level). Occasionally I find this causes issues with dimensions or using the measure tool as Revit can't find the face in fine detail level. Changing to medium detail level always fixes the problem as you can now find the 'edge' of the element. Something to keep in mind for next time!