"It was just sort of an exercise in saying everything I needed to say about a whole lot of different stuff and I put off dealing with that.
"I was like, that's for future Ella to deal with."
Then came a message from Charli XCX, inviting her to collaborate on her track girl, so confusing from her acclaimed album Brat.
In the remix, Lorde opens up about struggling with an eating disorder and comparing herself to the singer-songwriter from Essex.
"Brat coming out really gave me a kick," says Lorde.
"Meeting her in that place of rugged vulnerability and people responding really well to that, I was kind of like, 'OK cool - this is a good thing to be doing'.
"I really suffer from this thing of not feeling my own power... and the remix just started me up and I was like, 'no no, people are listening and they care and your words carry real weight'."
Aside from its multiple awards, Brat also became a cultural phenomenon when it was released.
It featured in the US presidential election campaign and the Collins Dictionary, which crowned it word of the year.
Lorde performed the remix during Charli's Coachella set in California last month, with Charli even suggesting "Lorde summer 2025" could follow 2024's Brat summer.
Lorde says Brat also inspired her to refine what she wanted to say with her first new music in four years.
"It forced me to further define what I was doing because Charli had so masterfully defined everything about Brat," she says.
"And it's so amazing when a peer throws the gauntlet down like that. We've gotta pick it up and I've spoken to a lot of peers who all had the same feeling."
Lorde's lead single, What Was That, was officially released last week after being teased on TikTok, debuting in the UK Top 10.
Lorde says it gives a flavour of her upcoming album, where she's tried to reconnect with her younger self.
"I really went into it like, 'just make something for you, just make something you think is cool'," she says.
"It's not unlike how I was making music as a 15-year-old, just trying to impress myself.
"What Was That was the first song from this album that I wrote and was like, 'OK, I know where to go with this'," she says, describing the track as "Lorde canon" and "recognisably me".
"It's funny to be 12 years into your career and for people to have an understanding of your tropes and what you do."
The singer says she "wanted to lock people back in" to her sound after her last album, 2021's Solar Power, which she says was "a very different flavour for me".
"It's about going to the core of who I am in the purest way possible, stripping away anything unnecessary."
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