Basically friction and heat will cause the slide to locally weld itself to the frame, and then tear loose again.. causing damage.
it won't bind if properly lubed.
And modern stainless is better quality then early Stainless 1911 pistols, like the AMT Hardballer, which was the first
"Galling of the stainless steel was a common issue, as lubrication technology at the time of original manufacture of the Hardballers was not suitable enough to prevent it. Galling occurred due to the alloy used, as well as the fact that the same hardness of alloy was used for the frame and the slide. Usually, different alloys and hardening are used to prevent galling. Modern stainless guns are much less susceptible to galling. Galling is a condition whereby excessive friction between high spots results in localized welding with subsequent splitting and a further roughening of rubbing surfaces of one or both of two mating parts. Early stainless steel alloys suffered from this due to the breakdown of lubricants. Galling can be prevented by electrolytic nickel plating of the surface. Typically either electrolytic nickel plating the frame rails or slide rails will take care of the problem in virtually all cases."
More in depth info about galling
Galling - Wikipedia, the free encyclopedia