why dont the ripples in a dirtroad "auto-even-out"?

Factual Questions
1

Ok, we all know the tiny “peaks” and “valleys” (irregularities in general) you find on dirtroad … enthropy suggests that they should even out over time - as the stones in the peaks (lots of energy stored) should sooner or later be worn away by tires or shoes and then fill the valleys (less energy stored) …

but dirtroad dont seem to converge towards evening out …

whats going on here? :rolleyes:

any ideas?

thx al

2

In colder areas, frost heaves form irregularities in the road surface and they are constantly making the toad uneven in fall and winter. Also, you assume the road is made of uniform material down its length and it probably isn’t. The type and pack of earth and rocks can vary widely even over a short area.

3

http://www.straightdope.com/mailbag/mwashboard.html