I think, at least for me, skies are one of the hardest things to get to look right.
We all look at skies everyday. Whether we are aware of it or not, we have looked at skies a lot.
Especially in color images, I often find the sky fails in many images- mine as well as others. It is just a feeling that I have seen lots of skies, and none ever looked like that.
We also subconsciously know what things look like under different skies. If they don't match with our experience the red flags come out, and something just isn't right.
I never can really be sure what color a tree or flower is- they can be lots of colors. But I know what color the sky is.
In this image, as I said, I am not sure I would have noticed anything. But once told- I suspect the actual sky was a little darker. With that light of a sky I would expect a little more light on the climber- but maybe I am just overthinking this.
This is going to be a powerful tool. I have lots of images that will be better with a different sky.
gary