Composer vs. Performer

Which is more important – the composer or the performer?
Put another way, would you rather listen to a song that you really like sung by someone you don’t like? Or would you rather hear a singer that you like sing a song that you don’t like? Which is worse?
When putting together a classical music collection, should the emphasis be on the composers or the performers? Ideally, of course, you would like to have the best of both worlds. But that is not always going to be the case and everyone has different tastes.
Right now, I am putting most of my focus on the composers simply because I am not all that familiar with who the good performers are. I am beginning to recognize some names through sheer repetition – Vladimir Horowitz, Isaac Stern, Itschak Perlman, Yo Yo Ma, and so forth. And so if I am looking for a piece by Brahms and it is played by someone I recognize, I consider it a bonus.
I wonder if in the beginning people look to the composer first and as they become more experienced with the music they begin to favor certain performers and follow them regardless of who or what they are playing.
I think this is a phenomenon that is rather unique to classical music because it has so much of its history outside of the recording era.
Imagine for a minute that the Beatles had composed all of their songs before the recording era. What if we had all their songs, but none of their performances and had to rely on other people to play their songs for us. Does Elton John do the best version of Lucy in the Sky with Diamonds? Does Aerosmith do the best version of Come Together?
That is what it is like with Beethoven, Mozart and most of the other classical icons. We have their music but no recording of them playing it. That used to be the norm, even when they were alive. But now we expect to hear the composer perform their own work in most cases. “Cover” versions are almost always considered inferior.
But in classical music we rely on cover versions of almost everything. So we make up for that by demanding that the performers adhere to the composition exactly like it was written and, in some cases, even use period instruments to recreate the sound that would have been made when the composer was alive.
Still, you can always hear subtle differences between performances. I got used to listening to one version of Beethoven’s Sixth Symphony and then when I ran out and bought a copy on CD years later was disappointed to find that it did not sound the same as I remembered. So I have acquired several more versions looking for just the right one.