If you fail by too much... You fall.
The gaps between jumping points (say, a river or canyon) don't have a defined area in between, it's just textures or impassible terrain.
In the case of failing to jump a river you'd need to have a character collide with the water and being swept away by it. New sounds and animations would be needed in addition to actually make the river function as some form of terrain so your character can get out again.
It wouldn't be impossible to do, but would require a fair amount of effort to include.
