New York Daily News, 9/17/17:
Why MTA conductors point out of their trains after stopping at subway stations
Conductors have a curious habit of pointing out of their trains when it pulls into a station.
SNIP
Follow their finger and you’ll see a black-and-white zebra-striped board hanging above them.
“You’re pointing to the safety of your passengers, to make sure that your train is completely and safely in the station,” said Shawna Robinson, a conductor who sits on the executive board of the Transport Workers Union Local 100. “You’re also pointing to let the (Metropolitan Transportation Authority) know that you’re doing what they trained us to do.”