UPDATE: purchased the Breville “the Compact Wave” and it is so quiet. I love it!! https://www.crateandbarrel.com/breville-the-compact-wave-microwave/s226034
UPDATE: purchased the Breville “the Compact Wave” and it is so quiet. I love it!! https://www.crateandbarrel.com/breville-the-compact-wave-microwave/s226034
They need to dissipate a lot of waste heat from the magnetron and have to use a fan.
Those other appliances don’t generate a lot of heat in a small space that must be air cooled.
I think they mean when closing the door.