I recently gained a student whose primary goal is to be able to sit at the piano and sight read out of a book while his family sings at Christmastime. It’s a great goal and I anticipate his being able to achieve it.
However, the piano can do so much more than play notes.
Many people wonder what makes a professional pianist different than an amatuer, both of whom play all the right notes in difficult pieces. What they may not yet hear is the harshness of an amateur’s tone versus the colors the professional achieves. Beethoven was one of many composers who composed pieces for solo piano that were still meant to have the grandeur of an orchestral piece. We give these pieces grandeur through tone color. We can twist the “piano” sound to more like a “bassoon” or “violin” or “flute” sound. I once heard a recording by Martha Argerich playing Bach where she started playing and her tone was so convincing that I initially wondered whether she was on a piano or a harpsichord. As the recording progressed and she brought out different colors, I was assured she was on a piano and quite impressed at her ability to imitate sound.
This is why the piano can be an orchestra by itself: it can play many notes at one time and produce the colors necessary with the volume necessary to equal the power of an orchestra, at least when played by professionals.