Why you won't hear Lorde's new song Liability on the radio

Lorde dropped a surprise new song Liability today - but don't expect it to start pumping from your radio any time soon.

The song, a heartfelt piano driven ballad, has the singer slurring confessional vocals above a stark instrumentation.

It can be considered the complete opposite of last week's party banger Green Light.

But whereas that song was the number one added track across all formats on New Zealand radio last week, it's unlikely Liability will get much airplay at all.

That's because the song hasn't been released as an official single and commercial radio rarely, if ever, picks up or playlists deep album cuts.

It's expected Lorde will perform the new track on Saturday Night Live this weekend, along with Green Light. The show's format requires guest musicians to play two songs.

The song is also pulling double duty and acting as an enticing incentive for fans to pre-order the upcoming second album Melodrama ahead of its release on June 16.

Those that do will receive an instant download of both the new songs.

The singer also appeared on Zane Lowe's Beats 1 radio show, where she revealed that Liability was about fame and learning to love herself.

"I had this realisation that because of my lifestyle and what I do for work there's going to be a point with every single person around me where I'm gonna be a tax on them in some way," she said.

"I was in this cab alone listening to Higher by Rihanna because ANTI had just come out. And I had a little cry and I was just like, 'It's always going to be this way, at some point with everyone it's going to be this way'.

"I was like, 'you know what, I'm always gonna have myself so I have to really nurture this relationship and feel good about hanging out with myself and loving myself'."

Lorde said the song felt "starkly truthful" and that she was keen to keep writing from a place of youth.

"There's such a youth to the writing, and I love that because I am 20, and I'm an idiot, and I'm determined to keep writing from that place," she said.