Description
The MEASURE_DIRECTION option was chosen as the Calibration Direction parameter, 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 tool run, and identify which polylines have the issue. Edit the vertices of those polylines and ensure that they have monotonically increasing or decreasing measures.