...and my career. I cannot afford to breathe incorrectly. Yet I have been, perhaps for years. Habits change and erode over years, imperceptibly. When I went to an Alexander teacher to get some help with posture to relieve neck and shoulder pain, I ended up learning how much tension I was holding in my torso and neck. And you can't breathe with a tight torso. Nope.
During many, many solo performances in my career, I had to fight my body's compulsion to breathe in order to finish some phrase or other. (This happens more often when I'm playing solo in front of the orchestra and standing. When sitting in the orchestra, there is more time to recover from each improper breath)
Wind players often suffer from "bad air" remaining in the lungs after they breathe. A breath may be convenient or musically necessary at a place where the lungs are not yet empty, so the new air mixes with the old, stale air. After a few more breaths like this, the air in the lungs is full of carbon dioxide. The body will then being to convulse to try to breathe, even in the middle of a phrase. I have had to overcome this desperate reaction and continue until a more suitable time to breathe.
The solution is to plan proper exhalation at certain times, and to take smaller breaths so as to fully exhale the at the end of a phrase. But proper breathing, where the muscles inhale and exhale much more efficiently, also helps to maintain a better balance of good and bad air. It helps keep un-necessary tension out of the chest, affording more freedom of breath.