Sure, someone writes the lyrics, someone else might write the melody, but - do they write *all* the music? If the guy writing the melody can only play guitar, someone's gotta come up with (for example) the drum parts and the bass line? Like, I dunno, the drummer and the bassist?

Seems like some guys in bands get screwed, and one or two guys get all the glory...

Sometimes one person might end up writing all the music, even the drumming and the bass lines. Band members get credit for performing this certain part of the song in the studio, but when writing music, it's probably easier for one person to do it instead of having everyone pitch in.

There are stories where the band would say that one member did this, and others did this, and that some help with the lyrics and melody...I don't know, I usually see two people actually writing the songs.