I used the following link to create labels with leaders, but since I have a polyline layer I used a different expression for the Geometry Generator:
make_line( centroid($geometry), make_point("auxiliary_storage_labeling_positionx", "auxiliary_storage_labeling_positiony") )
It appears to work, but looks quite ugly, where some of the leaders go past the geometry centroid as follows:
And others fail to reach it:
Why does this occur and how can I fix it?