She told Hosking she's not setting a target for how much she wants to lift Labour in the polls.
"Ultimately, when you're in opposition politics the goal is to be in government. What we do absolutely need to do though is lift our game. That's clear, that's clear to everyone. I don't think anyone would dispute that."
Ardern said she's taking the next few days to look over the state of the campaign, before making any changes.
She said she wants to improve on Labour's strong platforms for the issues of health, housing, and education.
"What I'll be looking for is just a couple of areas in there to put a bit of emphasis on things that I think people will be wanting to hear, a bit more vision and hope for the future."
Ardern says her new policies will have more vision and hope for the future.
Meanwhile, New Zealand First leader Winston Peters told Newstalk ZB's Nadine Higgins that Labour was too hasty in changing leaders based on poll results.
"Your job in politics is to create polls. Your job is to get the outcome that you seek based on the things you believe and also the strategy and planning behind it. The last thing you do is be a poll-driven fruitcake as they say.
"It's a very desperate move, if you think about it. A move like that is so filled with risk you have to wonder why they did it."