[Spoilers]Shock values
It used to be film-making taboo to show children dying, as that'd have made any scene suddenly take a dark turn.
Well as time passed, viewers are getting more and more accustom to the formula that it didn't take long before this can of worm need to be opened to once again brings out a "fresh" experience for the moviegoers.
I have to say it kind of worked. I found myself being the cynic going about how: "Of course the dad died right there but the kid lives from falling off 7 floor building, they don't got the balls to kill off a kid. Now Andy Lau's going to take care of her just like before." Before BAM, she didn't make it.
That's not to say the twists aren't good in the movie (like how Andy Lau calling the cellphone for another attempt at betrayal, only to have the guy saved yet again by luck", but the Final Destination car crash at the end was a real eye-roll.
But at least they didn't make it so the guy sent the video to his ex-gf while he was hiding in the taxi. Then the ex-gf exposes Andy Lau (that probably be too much a "meta" shoutout to The Departed.)