Most people stand facing the train which they are waiting for.
That is a high risk, low upside decision.
While the chance that someone will push you from behind into the tracks (with or without malicious intent) very small, the downside is irreversible.
The simple choice to stand with your back to the train is obvious.
The chance that you will not notice your train’s arrival (trains are quite loud; everyone else standing around you is unlikely to stand still when they arrive) when facing the center of the platform is also very small, but presents little downside. The absolute worst-case scenario is that you miss your train.
If you think about it, facing the train is for suckers.
It makes me wonder why so many of us take the sucker route.