Sia Originally Wrote Chandelier For Rihanna

Sia does no like the spotlight. Because of that, the singing star has been reluctant to perform her own material.

Her biggest hit ever as a writer, Rihanna's "Diamonds," almost led to her giving her current smash hit "Chandelier" to the mega-star. Sia, however, changed her mind and decided to perform the song herself.

"I usually think, 'Oh this would work for Rihanna, or this would be a good one for B or Katy,'" Sia told "On Air with Ryan Seacrest." "But this time I was like, 'Uh oh I think I just wrote a full-blown pop song for myself by accident!'"

"My friend Jesse Shatkin and I were jamming in the studio -- I was playing piano and him on the marimba -- and this gem popped out," she said.

In an appearance on the Hoard Stern Show she explained that the song was too personal to give away. It related to her past drinking problems.

Sia, who does not like her face to be seen, has performed recently on a number of talk shows using surrogates including Lena Dunham while she sings.