Like most household tricks, this one works best when used with a little common sense. The oven should be completely turned off before the lemons go in, and if you leave the door open, it only needs to be slightly cracked, not hanging wide open all night. The idea isn’t to just to let the oven air out a little while the lemons sit inside. A lot of people try this after cooking something particularly greasy, smoky, or heavy-smelling, when the oven tends to feel a little more “used” than usual.
Then the next morning, you simply remove the lemon halves and give the inside a quick wipe if needed. That’s really why this trick has lasted. Not because it’s magical. Not because it replaces actual cleaning. But because it’s one of those strangely simple little habits that can make an oven feel fresher with almost no effort at all.
And once you’ve tried it, it becomes much easier to understand why some people keep going back to it.