Use it or lose it.

Abilities that go unexercised tend to fade, and the saying treats this as a rule about nearly everything we can do, from muscles to languages to friendships. The phrase has no known author, which fits its character as a piece of folk wisdom passed along in gyms, classrooms and workshops rather than a line from any one thinker. Its logic is simple: skills are not possessions stored safely in a drawer but living capacities that need regular activity to stay alive.

It rests on a very old and practical view of human nature, one that echoes Aristotle's idea that we become capable through repeated practice and that excellence is a habit rather than a gift. Modern science gives it support. Muscles weaken without load, and the brain strengthens connections that are often used while letting neglected ones fade. Anyone who has tried to speak a language they studied years ago knows the feeling.

A person today might apply it by choosing one skill they care about and giving it small, regular time. Someone who learned Spanish in school could spend ten minutes each morning reading a news article or chatting with a language partner, rather than waiting for a perfect long study session that never comes. The point is gentle persistence, not guilt.