했어야 했어 (Shouldn't Have)

Baek A-yeon delivers this track with a kind of controlled devastation — her voice is bright and clear at the surface, technically precise, but there's an undertow of something rawer pulling beneath each phrase. The production is mid-tempo ballad territory with a contemporary K-pop sheen: clean piano chords anchoring the verse, a light electronic pulse threading through the pre-chorus, then a full orchestral release when the chorus finally opens up. The emotional logic of the song is regret in its most excruciating form — not the regret of doing something wrong, but of not doing something right, of standing at a crossroads and choosing stillness when movement was needed. The melody has that characteristic Korean ballad quality of climbing just a half-step higher than you expect, wringing an extra measure of ache from the listener. Her delivery in the bridge is particularly striking — she pulls back where another singer might push, and that restraint makes the feeling land harder. This is a song for the moment after a relationship has already ended, when replaying every decision reveals exactly where it could have been saved. It belongs to that specific 2 a.m. headphone session when honesty with oneself is unavoidable.