Your list of Global Parameters in a project can get very long and messy - so eventually you'll need to do some tidying up.
Global Parameters Dialog Box
The Global Parameter dialog box has a 'Delete' function, not surprisingly - a red cross icon, next to the modify and create new icons.
A Global Parameter (GP) can be used in formulas for other parameters, and it can be associated to dimensions or elements in the project, so you need to be careful about deleting them - more so than in the family editor (where you have a better chance of knowing where they'd been used).
If a GP is deleted, then any formulas using that GP would also be cleared - it gives a warning, which is invaluable
If a GP is deleted, where it has been associated to elements, it also gives a warning with a number of elements to be affected - if you proceed all those associations would be lost. By comparison, in the family editor deleting a parameter would affect only that family, whereas with Global Parameters it could affect the whole project. So, be very careful
Elements in the Project
Elements in a project could have GPs associated with them, and deleting the element would obviously break/lose that association. It is important to know when this is happening - or better still, beforehand. When a dimension is deleted, it will warn you about constraints; it does the same thing for GP associations to dimensions.
If you delete an element that has a GP directly associated to one of its properties, it does not warn you - Revit just goes ahead and deletes it. For this reason it is important to be able to check which elements have associations
Checking GP Associations
When you select an element that has GP controlled dimensions attached to it, all the related GPs show up on screen, including the label names. You can hover the cursor over any of the highlighted constraint dimensions for more detail in a popup tooltip.
It is a mystery why all those extra label names appear in this situation but not when you select an actual dimension. Sometimes it gets very messy and confusing
More on checking GP Associations by scheduling and view filters to follow . . . .