And, as mentioned by Greubau, the default doors open inside thus making it easier to break into the apartment while the steel doors open outside.
Friendy, I'm afraid I'm forced to disagree. Seriously this time. According to safety regulations all doors in apartments, schools, hospitals, etc (that is where there are many people) must be pushed to open, not pulled - should there be a fire, there may be people throwing themselves against doors in panic. Think about it, it makes perfect sense.