Humans, indeed every animal, has an impact on the terrain. It isn't just the scuffing and plowing effects of traffic. A lot of damage is a result of simple compaction.

I some types of soil the tendency is that rain soaks in but remains dispersed. This water only very slowly migrates downhill. If you pound down a path in the direction of even a very shallow slope the water will tend to slow toward the path and then preferentially use the compacted path to travel down the slope. This flow becomes a steady stream when it rains and the stream cuts the path deeper. In some soils a small path can become a gaping gully in a matter of days if the rain is heavy.

The only way around this is to recognize the relative delicacy of some areas and to limit the numbers of people who travel through it, to establish some way to make sure people don't follow the same path, or to get people to avoid the area entirely.