Many composers--Richard Wagner, for example--didn't have a shred of humility and most composers tend not to suffer fools too gladly, but there are some examples of humility from composers that are very striking. One of my favorite quotes is from a letter Beethoven wrote regarding his String Quartet in C# minor, op 131. This quartet is widely regarded as one of the finest, perhaps the finest, ever written. The great musicologist Joseph Kerman says that the finale movement is the most perfect finale in any genre. What did Beethoven say about this superlative work? That it was "less lacking in fantasy than my other music." We find an echo in Osvaldo Golijov who said in an interview: "I'm a second-rate composer, but a really good second-rate composer." That sounds absurd, but it has a lot of truth in it. Golijov is one of the best younger composers writing today, in my opinion, which puts him one rung down from those very, very few first-rate composers: Bach, Beethoven and probably Shostakovich. Others would say Mozart. A few crazy folk would vote for Chopin or Stravinsky or even Wagner, perhaps. Speaking of Shostakovich, there is a great quote from him too. Regarding the first movement of his String Quartet no 15, the last he wrote, he gave a performance suggestion to the quartet in rehearsal for the premiere. The first movement, one of six movements, all adagio, is very static, like a fugue in slow motion, it unfolds very slowly. He said they should play it "so that flies drop dead in mid-air, and the audience start leaving the hall from sheer boredom".
I know exactly what he means and I love that he said it that way. But the truth is that this movement is transcendent, sublime. Here, have a listen:
How does he do that? From the first note, you are captured. Oh, and here is that finale to the Beethoven C# minor quartet: