It’s not typical for apartments to go from 0-full in a very short period - people are in 12+ month leases elsewhere. Also, they have lease turnover constantly. It’s not to say 10 open units have been sitting there empty since it opened. It could be 10 units that are coming up on an open lease but aren’t open right now.

Plus, you can buy condos for the same price as a mortgage - hence the high demand in those other buildings.

Like it or not, there’s demand.