count of desktops only returns 1 Any idea why the following script would only return 1, when I clearly have more than one Desktop open?

tell application "System Events"
    set n to count of desktops
    display alert n
end tell


I have even tried it with JAX JavaScript and also get 1. 

Note: For reference I am using El Capitan (MBP Mid 2012)
'desktops' are 'monitors' not Spaces.
There's no programmatic way to count Spaces, short of using the GUI, which is very hit &amp; miss.