Music is an experience.  Knowing how to play your instrument and the notes on the page is good, but that's not what makes a great performance. A functional product is a given to the user. It's when the designer can empathize with the user and create a real solution to their problem that makes a good experience.

Music teaches you to break down complex problems into digestible bits. Even the best musicians in the world practice their scales every day. That's because it helps them look at sheet music with more black notes than white space and identify the fundamental patterns so it's not as intimidating as it looks. I'm not scared of complex user problems because I know how to break them down to find the solution. 

Getting a 95% on a test is great.  Play 95% of the right notes?  You're fired. Musicians have a heightened sense of attention to detail - it's part of the craft. They have to be deeply focused on the present phrase AND thinking about what's coming next. High-pressure situations is our forte (no pun intended).  

As first chair flute in a symphony of 80+ people, I had to know how my part fit into the bigger picture. It requires great communication and collaboration to achieve the common goal in both a symphony and as a UX Designer. Understanding the roles and needs of everyone on the team, or the stage, is imperative for success.

I wrote a hundred versions of the song before I wrote the best version of the song. Designing a product requires patience and an inquisitive, open mind. You have to be determined enough to play with many different solutions before you find the best solution. When composing or designing, you have to be open to feedback and flexible in making changes.