It could be that, if the artisan were male, the thought of chiseling on a particular area may have sent chills up his spine with every strike. In that case, it could be easy to understand how one might unintentionally knock off a larger piece than they intended. If that area were the last area worked on, rather than scrapping the entire work, one remedy may have been to just tone down the size of that portion of the body. Alternatively, it could just be an accurate reflection of the males around at the time.