Change Button Border Properties on IBAction

Question

Why does this allow me to change the bordered state but not the border width (or other border properties)?

NSButton *button = (NSButton *)sender;
[button setBordered:false];
[button setBorderWidth:5]; 

Answer 1

The setBorderWidth: method does not exists, check the NSButton Class Reference.
In other words, NSButton does not support changing the border width (by default).
The setBordered: method defines wether the button has a bezeled border.
Setting setBordered: to false removes the complete bezel, for example:

The setBordered: method might be confusing therefor.