Previously NZ decided against face masks due to a well researched review of Science and policy around face masks, published by NZ Health. The link to the report is now dead.
They have now recommended all NZ citizens to buy masks for the 2nd wave to use in phases 2 and 3.
Note they have not only gone against their own scientific review, but increased the scope of masks to include source control from asymptomatic persons speaking and laughing.
2nd wave as predicted.