Valve question

Is there any value to the condition of the face of the valve? I, through
ignorance, am calling the flat (the part that faces the piston) the
face. I can understand the need for the valve to seat properly, but if
the face is pitted, should you replace the valve? What about concentric
rings on the face? What do they indicate and should they be replaced
also?
Thanks!

Bill Mantz
Roanoke, Va.
1971 Midget (soon to be daily driver, I hope)
1959 Bugeye (in progress)