"With Miley, it was a bit of a merger. I heard this wonderfulness bleeding through the doors and a friend of mine, Dr. Luke said to come and listen. And I was like, who is that? He just said, 'keep listening' and then he said, 'guess who it is?' I was like, Björk. Nope. Is it Portishead coming back?... It was Miley Cyrus. Then Miley walks in the room and I was like, this shit is fresh, we have to collaborate. Then she got on and added her vocals for 'Fall Down'."
— will.i.am describing his collaboration with Cyrus.
"Fall Down" marks the first of three collaborations between will.i.am and Cyrus in 2013. In October, he was credited as a songwriter and producer on the track "Do My Thang" from her fourth studio album Bangerz, while Cyrus was featured on his track "Feelin' Myself" from the reissue of his fourth studio album #willpower in November. will.i.am first became interested in collaborating with Cyrus after hearing an earlier version of her single "Wrecking Ball", and came in contact with her through producer Mike Will Made It.
"Fall Down" was first released on April 16, 2013, preceding the release of #willpower in the United States. It served as the follow-up to will.i.am's earlier singles "Scream & Shout" with Britney Spears and "#thatPower" with Justin Bieber, and served as a promotional single from the record. will.i.am and Cyrus promoted the song with live performances on Jimmy Kimmel Live! and Good Morning America in June. It was released to Australian radio stations in July 2013 as the third single from the record; an Italian release followed on September 6.
In contrast from the electronic dance music elements presented in "Scream & Shout" and "#thatPower", "Fall Down" leans towards an urban contemporary musical style. The chorus incorporates electropop elements, while the verses tend towards a hip hop format, while the track itself culminates with an orchestral bridge. will.i.am mentioned the bridge as his favorite piece of #willpower, and described the overall song as if "Quincy Jones just sneezed on it." Lyrically, the track describes the positive impact a couple has on each other, as seen in the lines "Girl, you're like an elevator cause you always pick me up / Girl, you're like a doctor when I'm sick you always stitch me up".
Critics compared "Fall Down" to previous tracks by Kesha (pictured), who frequently collaborated with Dr. Luke.
"Fall Down" received generally negative reviews from music critics, who were disappointed with its overall production. Writing for AllMusic, Fred Thomas was displeased that featuring "big gun" Cyrus still resulted in a "manufactured disposable pop moment", and further elaborated that the song felt like one of #willpower's "interminable 15 tracks [that] were written in the studio moments before they were recorded." Sam Lansky from Idolator shared a similar sentiment, opining that Cyrus felt "mostly phoned-in" by comparison with the "emotional punch" Cyrus delivered on her collaboration with American rapper Snoop Lion, "Ashtrays and Heartbreaks". Andy Peterson of Contactmusic.com criticized the production of the track, stating that listeners are "treated to the sort of identikit trance-plus-autotune sound that's been annexing American teen culture in the last couple of years".
Writing for entertainment.ie, Karen Lawler criticized lyrics like "you could be my Coca Cola, let me sip it up" for acting as a substitute for the "articulate rhymes on which [will.i.am] built his reputation", Brent Faulkner from PopMatters agreed that the lyrical content was sub-par, and called the song itself "utterly ridiculous". Mesfin Fekadu from The Huffington Post called Cyrus' contributions to the song "forgettable". Gregory Hicks of The Michigan Daily compared "Fall Down" to "Die Young" and "Crazy Kids" by American recording artist Kesha, all three of which were produced by Dr. Luke, which Hicks felt indicated that "Dr. Luke’s production and writing continues to dwindle as he copy and pastes his work with Ke$ha onto this will.i.am track."