Some birds are trained to pose like that, with others it is breeding. Many people like the extreme posture and wing carriage and therefore breed for it . I do not, I am more concerned with size and color in my flock.My birds don't stand like that.Their posture while still upright is more like a "normal" chicken because I prefer it. IMO it is more natural looking.
Hens go broody when you don’t want them to… and won’t go broody when you do. 