Not sure, they were very popular in Italy when I was young. No electric kettle, we used gas stove ones. Heating was either radiators (slow) or wooden fireplace

Not sure, they were very popular in Italy when I was young. No electric kettle, we used gas stove ones. Heating was either radiators (slow) or wooden fireplace (only heats nearby), so maybe that's the main reason for its popularity, inefficient heating.