Wonder Girls released their digital single and music video for Why So Lonely, a heartbreak song that has a taste of reggae music and an island feel of the old days. The song is about how the girls are in a relationship with a guy but they still feel lonely around him.

They sing that he hasn't changed and that he doesn't show any feelings towards her. Chances were given, but this is the last time the girls will give him a chance. It can be clearly seen in the video that the girls are angry and bitter as they show some violence toward the "dummy" boyfriend. Even so, they were still able to keep that sad personality.

The video is beautifully filmed with great colors, giving an old vintage vibe, as well. Three of the members, Yubin, Hyerim, and Sunmi, had contributed to the composition and lyrics of the song.