A man inside an insulated metallic cage doesn't receive a shock when the cage is highly charged. Why?

A man in a metallic cage is not affected even when the
cage is highly charged due to what is known as the Faraday cage effect. In a state of
equilibrium, charges are as far from each other as possible. When charge is introduced
into a conductive sphere, which can either be hollow or solid, the charge moves due to
the forces of repulsion between like charged particles and arranges itself on the outer
shell of the sphere. They are the farthest from each other when arranged in this
way.

Due to this the charge inside a metallic sphere is
always zero. This is also the reason why a person in a charged metallic cage does not
receive a shock. This is the reason behind people advised to stay inside their cars
during a lightning storm. Even if lightning strikes the car the person inside is not
affected by it.