This piece has a relaxing mood about it. It works because:
1. The neutral colors keep it mellow,
2. The opacity of the letters prevent any of them from lurching forward,
3. The floral design of the underline gives it a sense of authority, yet maintains its grace. It makes me think of someone insisting one be quiet, but only because the baby is sleeping :)
4. The period at the end of the darkest yet smallest word "quiet" has the same effect as the line, and
5. The descending words (or ascending, depending how you look at it) give it a sense of noise fading away.