"I think it's just the nature of an event like this," she told The Guardian.
"There is very little time to sit and think in those terms. You just do what feels right.
"I knew what I wanted to say about that straight away. But, no, I didn't think about particular words. I just thought about sentiments, and what I thought needed to be conveyed."
The Herald revealed yesterday the words that got the most resonance in her speeches were drafted by Ardern herself.
Phrases such as "you are us", of the migrants and refugees killed in the attacks, and her direct message to the gunman, "You may have chosen us - we utterly reject and condemn you", were all Ardern's.
Staff would free her up for about half an hour before each media appearance or speech to let her rewrite and add to the prepared statements.
Ardern's response was also seen as a contrast to how other world leaders have behaved following mass shootings.
Ardern was quick to define the act as terrorism. She refused to speak the name of the accused gunman, and quickly moved to crack down on New Zealand's gun laws.
Her choice to wear a hijab also drew global praise, but again, it was not something she deliberated hard over.
"For me it was just a mark of respect," she told The Guardian.
"It was naturally what you would do. So, no, I didn't really think about that, either.
"It felt incredibly sad but completely obvious as well, that there would be those who would be worried. You know, the Muslim community was so obviously targeted, and they wear their faith so openly."
Ardern wore black – the colour of mourning for Muslims - the day after the shootings.
She dressed that way for several days.
Ardern told The Guardian the issues around Facebook, where the attack was livestreamed, were "global".
"We're asking for them to invest in ways to prevent the kind of harm we saw in the aftermath. And, let's be honest, in the lead-up, too."
In the hours after the attack she was contacted by many world leaders, including United States President Donald Trump. When asked what the United States could offer New Zealand, she famously responded: "sympathy and love for all Muslim communities".