Bad roads act as filters. They separate those who are sufficiently appreciative of what lies beyond the blacktop to be willing to undergo mild inconvenience from that much larger number of travelers which is not willing. The rougher the road, the finer the filter.

Joseph Wood Krutch (1893-1970) American educator, writer, critic, naturalist

Baja California and the Geography of Hope, Introduction (1967)
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This was a thought that Krutch adapted and repeated in a number of writings.

In The Forgotten Peninsula, A Naturalist in Baja California, Prologue (1961), Krutch quotes an acquaintance as saying, regarding the peninsula's unspoiled beauty, "Baja is a splendid example of how much bad roads can do for a country." This quotation was often misattributed directly to him, and he adopted the sentiment.

Late in his life (Winter 1967-68), Krutch was interviewed by Edward Abbey for Sage magazine (reprinted in One Life at a Time, Please (1988)), and discussed the proposed development of the new Canyonlands National Park:

Too many people use their automobiles not as a means to get to the parks but rather use the parks as a place to take their automobiles. What our national parks need are not more good roads but more bad roads. [...] There’s nothing like a good bad dirt road to screen out the faintly interested and to invite in the genuinely interested.