You do not appreciate balance until something makes standing complicated.

Balance is doing enormous work at every moment and receives no credit for any of it. You only meet it when something disrupts it: an inner ear problem, an injury, an unfamiliar surface, age. Then the simplest act of standing becomes an operation requiring attention, and you understand what was previously being handled for free.

Balance is also trainable, and almost nobody trains it until it is failing. Stand on one leg while the kettle boils. Thirty seconds a side is enough to keep something you would badly miss.