  The low kinetic friction between ice and numerous counterbodies is commonly
attributed to an interfacial water layer, which is believed to originate from
pre-existing surface water or from melt water induced by high contact pressures
or frictional heat. However, even the currently leading theory of frictional
melting appears to defy direct experimental verification. Here we present
molecular simulations of ice interfaces that reveal that ice surfaces liquefy
without melting thermodynamically but mostly by cold, displacement-driven
amorphization, as implied in the idiom constant dripping wears the stone. In
fact, the ratio of wear and shear rate for ice at -10{\deg}C is even smaller
than that of Niagara Falls averaged over one year. Despite efficient
self-lubrication, small ice friction coefficients as observed during the
sliding of hydrophobic solids over ice, appear possible only when the
counterfaces are smooth and allow water to slip past them.
