I wonder if the reason they don't make sense is the lack of common appliances and 'plastic dry cleaning covers' around the globe. Every iron has a dot-based tem

I wonder if the reason they don't make sense is the lack of common appliances and 'plastic dry cleaning covers' around the globe. Every iron has a dot-based temperature setting (alongside others, generally), but not everyone knows what a mercury thermometer looks like or if that means 'temperature setting'.