You should call 911 when a house is on fire.
On his way to work, Jack spots a house burning.
Jack wants to get to his job meeting on time.
Jack stops for a second, calls 911 about the house fire, then takes a short cut to his job meeting.
Jack stares for a second but then ignores the fire and drives fast to his job.
The house and people inside survive the fire.
The house and people inside don't get the help they need and perish.