When's enough ?

[YELLOW]

I think Gary nail it right on the bottom!
But to add to that I think if there is an expected number of swats, then the spankee is mentally taking an indurance test. If instead it is unknown how many swats they will recieve, then the discipline becomes more intense mentally.
As a spanking is being administered you can notice the levels of change in attitude. The responce should be the signal of when the spanking has done its purpose.
And, I agree, it should never be brutal.