Description
A MEASURE_DIRECTION was chosen as the Calibration Method, but the measures on the polyline were not monotonically increasing or decreasing. As a result, the direction was calculated for those polylines based on whether most of their measures were increasing or decreasing.
Solution
Examine the log returned with the execution of the tool, and identify which polylines have the issue. Edit the vertices of those polylines and make sure they have monotonically increasing or decreasing measures.