I can only think of a couple of sensible reasons why DOX is not flooded with locals, expats and tourists. Location is one. Whilst Prague 7 is hardly the end of the earth, DOX is not located near very much else like it (aside from Veletržní Palác which is similarly under-frequented) and tourists in particular do not have much of a reason to visit. Additionally, the Czech Republic is not regularly enough associated with modern art and design. Growth in this area is often noted in other cities such as Berlin and Amsterdam, but less so Prague. Tourists to Prague visit more commonly to see the old sights, rather than the new.