Why Can't Americans Do a New Zealand Accent?

Why can't Americans do a New Zealand accent? Doing another accent is definitely tough, but with all the money and resources at Hollywood's disposal, the results of American, and other nationalities, when trying to do a New Zealand accent has usually been pretty bad.
In this video, we're going to listen to some famous examples of well-known actors from the US and the UK try their "best" to do a New Zealand accent on screen. Brace yourselves! It gets pretty rough.
#EnglishAccents #AmericanAccent #NewZealandAccent
1:21 Sir Anthony Hopkins, The World's Fastest Indian
4:48 Dee Bradley Baker, Star Wars The Clone Wars
6:47 Ben Kingsley, Ender's Game
7:48 Steve Guttenberg, Don't Tell Her It's Me