Q. What are the advantages of a double pole switch?

Answer

When an appliance is plugged into a double pole socket both the live and neutral wires are switched. The load circuit can be safely isolated with a twin pole switch because it toggles both the live and neutral. If a user wants to turn off the power in both the live and neutral wires at once a user will need a double pole switch; with a single pole switch turning off the power in the live wire also cuts power to the neutral wire. Is there any reason why a single-pole switch couldn't be used instead of a double-pole one?