Here's why:

* Distance vs. Displacement: You're mixing up two concepts:

* Distance is the total length of the path traveled.

* Displacement is the straight-line distance between the starting and ending points.

* Zero Displacement, Not Zero Distance: If motion starts and stops at the same location, the displacement is zero. But the distance traveled can be anything other than zero. Imagine running around a track:

* You start and end at the same point, so your displacement is zero.

* But you still covered a significant distance by running the entire track.

In summary:

* If motion starts and stops at the same location, displacement is zero.

* If motion starts and stops at the same location, distance can be zero (if the object didn't move at all) or any other positive value depending on the path traveled.