How does the surface quality effect the cut edge quality?
A dirty, painted or corroded plate surface is detrimental for the cut edge quality, although this depends on the method.
For oxy-fuel and plasma cutting, the surface condition has a limited influence, during oxy-fuel cutting the speed might need to be reduced slightly if the surface is painted or corroded.
For laser cutting, surface quality is very important and a very clean (naked) plate surface near the intended cutting line is needed.