Why do stable nuclei never have more protons than neutrons?

(N/A) The stability of a nucleus is determined by the balance between the attractive nuclear force and the repulsive electrostatic force. The nuclear force acts only between nucleons (protons and neutrons) over a very short range. If the number of protons significantly exceeds the number of neutrons,the long-range electrostatic repulsive force between the protons becomes stronger than the short-range attractive nuclear force. Consequently,the nucleus becomes unstable and tends to undergo radioactive decay to achieve a more stable configuration.