When we refer to an Element's Settings or look at the Settings dialog box, there is an essential distinction that needs to be understood: Default Settings and Selection Settings.
Default Settings refers to the Settings of a particular Tool, prior to the placement of an Element - the Tool's Settings that are current once the Tool is activated.
Here: the Wall's Default Settings set to a Generic Exterior Wall Composite (note that the Wall behind is not selected):
Here: the Settings of a selected Wall (note the green-highlighted Wall selected in the background):
In ArchiCAD there are different Default Settings for every Tool. The Wall Tool can default not only to placing Walls on a specific Layer, but to a whole host of different default values: Wall Structure (whether Basic, Composite, or Complex Profile), Elevation relative to Home Story, Top Story Offset, Uncut Contour Pen, Structural Function, Position, just to name a few. We can "draw" a Wall in Plan in ArchiCAD just as simply as we used to draw a line in AutoCAD - start-click, extend, end-click. But there are quite a few more Settings, Attributes, and Parameters that we should look at before we place that Wall...or that Slab, or Roof, or Object, or even before drawing a 2Dimensional Element like a Line, Arc/Circle, or Polyline or Fill.
Sometimes the Default Settings for a given Tool don't seem to make sense - they don't align with our current intention - maybe even going to a Layer that is hidden or locked in our current Layer Combination:
A recent question about why this 0-3D-HIDE Layer was kept showing up as the default for several Tools is was the prompt to write this post. I inherited this Layer along with the Template when I started working as BIM Coordinator, and I use this Layer essentially as a Layer on which to hide things that I don't want to show up in any Layer Combinations. Should this Layer get renamed? Perhaps. Another topic.
So let's take a look at the Settings of some of the simpler 2D Elements, so we can begin to understand what is driving the Tool's Default Settings.
Maybe our Line Tool Default is going to one Layer, using one Line Type and Pen, the Arc/Circle Tool has a completely different set of Default Settings, and the Polyline Tool yet a third completely different set. Maybe we're beginning to think that ArchiCAD is confused and doesn't know what it is doing.
Let's fix that.
Pick one of those Tools, say the Line Tool. Check the box for Uniform Settings for Line Tools.
Then click the Favorites button, click a Line Favorite (maybe the thin one), then click Apply.
Since we checked the box for the option to use Uniform Settings for Line Tools, each of these three Tools' Default Settings will now be the same. They'll all use the same Line Type, Pen, Line Category, and Layer.
The Line Tools, the Text Tool, the Object Tool...these all get used for so many different purposes that there are going to be changes we'll need to make to the Default Settings for each of these Tools once we begin placing Elements - it is impractical to have a Favorite for every conceivable action we might wish to make in ArchiCAD. Use a Favorite as a starting point, check and modify other Settings as needed, then place the Element.
If we use the Eyedropper to pick up the Settings of an Element in ArchiCAD, we've just picked up that Element's Settings as the current Default Settings for that particular Tool. We often pick up Settings and Parameters that way in order to inject them into another Element sometimes without realizing that we are also changing the Default Settings for the Tool. In the Template, each Tool's Default Settings are set to appropriate "starting point" Settings for that Tool, but as we work in a Project, and as we use the Eyedropper to pick up and then inject Settings and Parameters into other already-placed Elements, the Tool's Default Settings "drift". They are not hard-set and unchangeable. When this "Default Settings Drift" happens, it is important to occasionally "reset" the Default Settings by re-applying an appropriate Favorite.
Let me know if any of this is unclear or if you have additional questions.