First floor apartments ... I don't understand why

It's been a long time since break-ins of first floor apartments were very common. But security concerns were not limited to 1st floor units. In the 80s I heard of burglars cutting through hallway walls to gain access to apartments. One of my favorite old NYC vignettes dates from the 70s. Check out a movie from the period, "the Goodbye Girl" you'll see brownstone apartments in now pristine UWS neighborhoods with multiple locks/dead bolts on the front doors.

Older people with trouble walking tend to prefer 1st floor units. Even in an elevator building, I think.

It's the garden - it looks like a really nice space - not worth a million bucks but it's great to have that outdoor space in nyc