Every mistake you make makes your next job stronger.

What a mistake leaves behind is more practical than character. It leaves a checklist. The carpenter who cut a beam short once measures twice for the next forty years and does not think of it as growth. It is simply where his hand goes now.

That is the mechanism, and it keeps working on days when you feel like nothing but the error. No wisdom needs extracting. The correction installs itself, quietly, and turns up next time your hand is on the same task.