[Fai Mao]

I have heard that most of that building is vacant because the floor space per-floor is actually too small for most businesses

[SunkenCiv]

The space just costs too much.

http://www.bbc.com/news/world-middle-east-18929271

http://www.independent.co.uk/news/world/middle-east/trouble-at-the-1bn-burj-khalifa-tower-spiralling-service-costs-see-landlords-falling-behind-on-their-bills-9127085.html