1. We are playing (talking) to the wrong audience.
2. We are not doing good enough work.
Everyone of us has had an experience when after a great and important work we did (in our opinion) we receive some harsh feedback. This can touch us very deeply, if we let it. The criticism can darken our day, it can produce writer's (composer's, or performer's) block. It can even take away our motivation to continue practice or otherwise to make or create things.
If you are playing to the wrong audience, then you simply have to find your own audience. That's it. But if your work can be improved, go do it, too.
Although the above 2 reasons are why we get criticized, it's sometimes very difficult to know which one of them (or both) you are experiencing in your situation.
So sometimes we want to hide and avoid criticism and settle for average stuff of trying not to offend anyone and please everyone. But the thing is - we can't please everyone. And if we tried - we will not matter to anyone.
The more productive strategy is to try to make things that matter deeply to a few. And if you receive a criticism from an individual whom you trust - pay attention. That's usually people who are on the same journey we are and who share a similar worldview we have.
But don't let the words of the critic destroy your passion and help you hide from important work. The words of the critic belong to the critic. They can only touch you if you let it.
If your work is important, you will get criticized. Some people will hate it and some will love it. That's personal. And this can be your compass - if you care enough about your work to get criticized for it, then you just learned something worth remembering.
The best way to improve and deal with criticism is to continue to take action and create things.