So, you are a beaver and after getting 80% through a relatively small trunk, you stop and then complete the task a bit higher up?

Assumption: the first cut was the lower one (would one cut the tree down first and then come and carve out the notch shown as a second pass?); did you measure incorrectly and realize you needed a shorter trunk length? Did we encounter some dense heartwood in our first cut and had to abandon the cut to keep our teeth?

Other explanations are welcome.