Why Not?

The song doesn't feature any lyrics, save a few sections of unintelligible vocals that are intentionally not tied to real words. They are sung in "hopelandic", which according to the website for Sigur Rós (where Jónsi is frontman) is "a form of gibberish vocals that fits to the music and acts as another instrument". The title of the song fits with a key theme in the movie it was made for, We Bought a Zoo. In the movie, main character Benjamin Mee is struggling to move on and find meaning after his wife's death.

Soft bells echo in and waft away leading up to a much fuller lead around 2:30. The tone is somewhat melancholic, but shaped into something optimistic by the vocals that remain warm. Even moments of silence can feel full, and there's no one specific message to make it that way.