In this case, the inspector general's report cited "systemic weaknesses in the adequacy of N.Y.C. Transit's station inspection programs" as the chief reason for this failure. One of the primary examples cited in his report is that despite repeated requests to repair the ceiling, which employees feared was unstable, the authorization to schedule the repair - not even to perform the repair itself - did not come until 3 years later.
As noted in "Why Many Slip and Fall On Snow & Ice Cases Fail in New York's Courts," one of the ways that the owner of a property can be held liable in negligence for defective and/or hazardous conditions on their premises is where they either knew, or, in the exercise of reasonable conduct, should have known about the existence of the defective condition, yet failed to take adequate, timely and reasonable measures to correct the condition.
I can hardly imagine a clearer case of negligence that is proven through constructive notice under New York law.