Poop is not a strong material. It holds together a little, but if you make it into a long cylinder and try to pick it up by one end, it will break. Similarly, as your fecal sausage creeps out of your bung hole, at some point gravity or other forces may get the best of it, causing one end of the proverbial loaf to pinch off before the whole thing is extruded. But, if the drop isn’t too high, a practiced shitter may well be able to lay it down as one intact crap snake.
TL;DR: Fecal matter is fickle matter.
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