Most Christmas ornaments that require electricity come with some sort of switch. If you have had a look at a switch recently, there is usually an "Off" and "On" button. Even if they aren't labeled it is pretty easy to figure out which button does which. If the Christmas tree doesn't light up, it's because the "Off" button wasn't pressed. This switch is something totally new though. There is no "On."
Instead, there is the standard "Off" and a strange "No" switch. Somebody got the spelling machine mixed up at the factory because Christmas should be a "Yes" season.