thats true liveinsin, but not always the case.
there will always be rare occasions where the bass makes its mark, like when the band dies down during the bridge and the bass just keeps driving it. or during a solo or when ur funking it about with slap blah blah..
but first and foremost as a musician, we should bring out the meaning of the song we are playing. what do the lyrics say? what should i play to bring out that emotion? am i playing too much? should i play more? what precise notes should i play and how long should i hold them? drive the band with 8ths, 16ths or play footballs (whole notes)? funk it up with some slap?
is what you're playing bringing justice to the song?
we should all take these into consideration. tastefulness, musicality, bringing out the groove, chemistry with the drummer, keeping in time, being creative all should come with the intention of making the music 'real' and with meaning to the audience. who can agree with me that a good song is one that brings out an emotion in you?
be it slow love songs or rock, we always talk about feel. this is what is MOST important to think about as a musician.