Do you mean open/closed to constant virus attacks? Or is it open/closed to constant headaches?
Or, may be, open/closed to daily crashes? And why not open/closed to the ires of monopolistics behaviors from Microsoft?

The Macs I am using are surely not closed to smart and reliable hardware design, nor are they to well thought out, efficient, and reliable software.

Please explain this often used old trick from the otherworld, I still have to get a clear answer to it.