Odd design choice. My oven turns the light on when the door is opened (in addition to a manual option). Maybe somebody “repaired” your oven at some point and replaced the door switch for the light with the wrong type? I had to be aware of this when I replaced a similar switch connected to a relay that turned a light on in a closet when you opened the door. I don’t remember the specific jargon at the moment, but it boiled down to whether or not the switch was open or closed by the action of depressing the switch. I think the language might have been something like normally open or normally closed.