Geologists also must account for whether the step was taken on a sloped surface or on a horizontal surface, and whether it was taken during dry season or wet season.

For example, estimating foot length from tracks can be inaccurate without these considerations the more erosion that has occurred, the larger the apparent dimensions of the track. Applications of this apparently larger foot size derived from an undertrack may lead to calculations of higher estimated hip length, and, as the authors point out, may also lead to slower speed estimates.