Wrong. See these links. The basic conditions:
https://www.immigration.govt.nz/new-...anent-resident The commitment to NZ criteria:
https://www.immigration.govt.nz/new-...zealand/slider
So already, your scenario is impossible.
But on to your question about expiry of residency. A NZ resident visa does not expire - it's for life, WHILE YOU ARE IN THE COUNTRY. However, with the residence visa comes two years of travel conditions, and 'travel conditions' is INZ's strange name for permission to re-enter NZ freely as many times as you want. And the travel conditions DO expire, two years after you were granted (or activated, if it was granted while your were overseas) your residence visa. So if you have expired travel conditions and you're in New Zealand, with no wish or need to travel overseas, that makes no difference to your life. But if you want to go overseas AND COME BACK, or your conditions expire while you are overseas, then without taking some other action about a visa, you can't re-enter the country. So in effect, your Residence would lapse, because you couldn't get in to take advantage of it. For what you might be able to do, if eligible, to readjust your visa status, see the bottom paragraph on the first link I gave, above.