We all know how cameras try to meter the scene as if it is 18% gray. That's why we should dial in +1 or even more when shooting on a snowy day and -2 for a night scene.
What about a cloudy or overcast day?
When you google "exposure compensation cloudy day" for example, the vast majority of the posts that come up say to dial in +1/3 to +1 EV. I think this school of thought stems from the underexposure possibility when bright cloudy sky is included in the scene, and should be stated as such. Otherwise, it is misleading advice. (The logic is similar to a snow scene.)
But assuming there is nothing in the scene (like white cloud) that can fool the meter, wouldn't you want to UNDEREXPOSE the scene? When you hold an 18% gray card in front of the camera on a cloudy day and meter, the camera will actually overexpose by trying to match the luminance of a bright sunny day. The result will be a bright, properly exposed picture, but not one representative of a cloudy day. That is why I think downward exposure compensation is necessary to catch the feel of a cloudy day. But I'm puzzled that this practice is not preached and wonder why.