And why is "It was never known why" incorrect?
I think it is because of determinative article "il" before perché. I can't give you a better explanation , maybe someone else will
Ok, thanks, I think I get it
Surely "It was never known why" would be a more accurate translation though, right?
I don't this so. "the why" is pretty common in French (I'm French) and it's probably the exact same one here.
I don't think madmcmurphy translation is wrong