There is nothing wrong "behind the scene." NZ batsman did not adjust to our pitches. For ex, yesterday, McCullum pulled Rubel and popped it up. When Ban was in NZ, McCullum pulled Rubel the same in more than one occasion for 6. And the way Taylor got out in the whole was just plain embarrassing. If I am not wrong, he was horrible against Ban spinners even in NZ.
And to add to those, our fielding and bowling has changed a lot, as just a month or so ago before this series BCB hired a bowling (Ian Pont) and a fielding coach (J Fountain). And they improved a lot in those 2 areas. I am sure you all noticed that. Specially the fielding. They held all their catches/chances (except yesterday), and that helped us defend those low total. Unlike in the past, those guys got lives and took the game away from us, just like Vettori did yesterday, almost.