Why the fascination with track design?

[Not Harry Potter]

Forgive me for being a little 'philosophical' with my first post, but I am hoping to learn what is the motivation for others for their interest in motor racing track design?
For me it was as a child, and the Observers book of Motor sport by Graham MacBeth, which had a few pages of mid 70's F1 circuits in bold B&W. I had another book which had a map of Brands Hatch, which showed the racing line, although I can't remember the title.
Since then I have been fascinated by motor racing circuits both old and new; either looking up real ones, re-designing them, or creating my own imaginary circuits. I love maps, and would often use street maps (the A-Z of London for example) to create imaginary street circuits, or look at an OS map of an area and work out where a road course, or a closed circuit might go. Any aerial photo of an aerodrome, my mind would be mapping out how it could be repurposed as a motor racing venue. Or I would simply use my imagination to create a location and with a literal blank piece of paper!
What is it for you?