The top of the kettle is unheated and insulated from the steam jacket. This reduces heat radiation and saves energy, and also minimizes the risk of burns to the operator.
This design also ensures that the food does not burn in the kettle spout when the kettle is emptied, which would reduce the quality of the food and cause cleaning to take longer.
The spigot makes it quick an easy to fill water for cooking and cleaning into the kettle.
The heating power is easily controlled and infinitely by using a dial.