[azakai]

A fence might also be easy to climb over, but can still clearly indicate where private property begins, and that trespassing there is wrong.

[rascul]

It's more equivalent to painting a line on the ground than a fence. Climbing a fence takes more effort than ignoring DNT.

[azakai]

Good point. But painted lines on the ground still have social power, for example in parking lots, where most people obey them. Hopefully the same is true for DNT as well.