"You Never Know" is a pop ballad that features the group's stripped vocals, minimalist arrangement and instrumentation provided by a piano and orchestral violin.
[6][7] "You Never Know" is a "heartfelt" pop ballad with minimalist arrangement and its instrumentation being provided by a piano and orchestral violin.
Writing for Billboard, Jason Lipshutz ranked "You Never Know" as the third best song on the album, calling it a "heartfelt balladry".
[12] Writing for the Young Post, Candace Kwan noted that the song's production allows "the girls’ vocals to shine".
[10] Sophia Ordaz of Slant Magazine stated that the track "sees Rosé, Jisoo, Lisa, and Jennie grappling with feelings of sadness and inadequacy".
[14] Hunter Church of The Young Folks named the track an "effective emotional closer" and "very unique in the context of the entire project" as it "manages to slow the pace down in preparation for the end of the record".
Writing for the same article, Palmer Haasch noted that the song shows "the members' individual vocal colors".