Interesting.....I have wondered about this too.
CREA's theory makes sense....because look at the lyrics of these songs (or singles) and you will find despair and sadness:
SEASONS
WHATEVER
TO BE
NEVER EVER
INSPIRE
GAME
HANABI
RAINBOW
H
A
M
&
SURREAL
AUDIENCE
ANGEL'S SONG
Makes a lot of sense.

LOL.....HAM.