In late nineteenth century England, horses were pretty much at the whim and whimsy of their owners. For those employed as carriage/cart horses, things were even dicier as to how they were treated. Very often a carriage horse was worked and whipped to the point of exhaustion, and they weren't always fed or properly cared for when their day was done. Add to that the cruel check rein, or bearing rein, which pulled a horse's head up and didn't allow them to pull the carriage properly, severely injuring their necks. This used up horses way too quickly.