Today's Random Thought

Why do walkers have hand-brakes? I saw a little old lady in Kroger with one that had two handbrakes on each handle. It's the same kind of brakes that comes standard on any bicycle. She was inching along at 6 inches per step. That's when I began to think that at this speed why not just let gravity take it's due course if a "sudden" stop is needed. The lady was already on that ragged edge between motion and stagnation.