I recall receiving admonishment as a child when crafting or baking, not to “throw out my mistakes.” That misshapen cookie was still edible; that cutaway construction paper scrap could be found useful in another project.
The other day while practicing, I was attempting a thorny passage up to tempo for the first time in a new piece. My fingers, seemingly having a mind of their own, followed a new finger pattern that I had not yet tried. When I got to the end of the passage, I was astonished at how well it had worked and how natural that “new” pattern felt. My “mistake” actually ended up being a better choice after all, and I decided to change my fingering to the new pattern.
Not all mistakes are as useful as the one described above. Most of the time, a mistake is not something that we wish to repeat. That being said, it can still provide worthwhile information, by highlighting an area of weakness that needs more practice, for example, or reminding us of where we need to focus our attention.
In either case, taking apart and considering our mistakes certainly helps make them less frustrating and makes practicing more creative and enjoyable.