Persona 5 and Translation

I have been playing Persona 5 for a couple of weeks and I absolutely adore this game. It's pretty, it's fun, the music is really cool, the voice acting is good... But some of the dialogue is a bit... lame?

I don't speak Japanese, so I wondered a few times why that was. Was it because Japanese is a difficult language to translate, or a bad original script, or a bad translation? 

Luckily this didn't put me off the game, and I have been thoroughly enjoying it. 

After reading this piece, I know what the problem is.  Spoiler: Translation.