I expect the building corporation need all the money 1st before building.
I can see Fuente Tower 1 across from my condo here in Cebu (rented). They were accepting down-payments for the 2nd Fuente Tower almost 3 years ago, and today i see no construction work happening at all. Meanwhile over in Ayala, apartments are rising very fast especially those which are adjacent or connected to the mall. These, i am sure will be completed before too long but of course they come with a over-inflated price tag and they are owned by the mall so the funding to build might be different.
The other downside with condos are reselling with the agents. When i was looking for a condo 3 years back, the agent wanted to deter me from anything pre-owned and go choose brand new (maybe due to commission from the developer). Either way, condos are popping up everywhere, so i guess the only benefit of buying pre-owed is that it is already built....