"We've done that [gotten four vaccines] because there's a number of them in development and some are really successful, some are less successful.
"So we've gone for four just to give us some options."
The PM also revealed what she had planned for Christmas - absolutely nothing.
"I have nothing planned - I have a lot of quality time with the 2-and-a-half-year-old planned. It'll be great."
And just like us, she's left her Christmas gift shopping until the last minute.
"I've been ordering things online," she admitted. "I haven't had a chance to go shopping."
This led to a mishap many of us are familiar with, she revealed.
"Awkwardly, one of the things I ordered got sent to the wrong place," Jacinda said, revealing the post got "one simple thing wrong" on her address.
"So, to the lovely builder in Grey Lynn, I'm sorry about that - thanks for popping it in my letterbox!"
Ardern also shared a message for Kiwis at the end of what has been "quite the year".
"I think the 31st is going to be less of a celebration of 2021 and more of a middle finger to 2020!"
"My message is thank you. Amazing people have helped get us here - scientists, epidemiologists - but none of it would have worked without Kiwis.
"It takes everyone to stop a virus and we've done that."
And she received a personalised gift from the radio hosts, who'd "heard Premier House needed a spruce up".
The PM wasn't so sure about that - "I'm quite happy to have a situation where it doesn't matter if Neve spills things!"
But then she admitted that while they'd "fixed the leaks", the house did have a "rodent problem".
"It's a heritage home but they're [the rats] in the roof which makes it quite difficult."
And the unique gift left the PM a little bit lost for words - a picture of Fletch and Vaughn dressed as 80s glam rockers posing on a couch.
She finally said it would be a "legitimate piece of decor for a carpeted garage" and "this is delightful, I have no idea what I'll do with it - it is rather large, over a metre in size.
"You look like blonde Jon Bon Jovis."