Why are they called ‘suicide doors’?
It's a slang term that the car companies don't endorse.
If you're getting out of the back seat on the drivers side and the door gets clipped by another car, a rear hinged door will kill you.
Back when those rear opening doors were common, it was thought that they would fly open in an accident. No one had seat belts then so a passenger could fly out through the opening, resulting in death by striking the pavement or getting run over by another vehicle. With conventional doors that swing forward, and unlatched door tends to stay closed at speed because of the force of passing air pushing on the door.