The real wisdom here isn't that failure teaches us—it's that mistakes become inevitable *only when we're operating at the edge of our knowledge*. A person doing exactly what they've done a hundred times before won't stumble, which is precisely why they won't grow. Consider a surgeon who performs the same routine procedure flawlessly for years but never attempts a new technique; her record is spotless, but her skill has calcified. Einstein's observation reverses our usual anxiety about error—it reframes mistakes not as evidence of incompetence but as proof that someone has finally ventured beyond the comfortable.