You can take the bandages off fast or slow. Most people prefer fast. It hurts more, but it lasts much shorter. Also, nurses prefer it this way as they want to shorten the suffering.
However, based on research, retrospectively people prefer taking them off slowly. The pain lasts longer, but it hurts less and the memory of it is not as bad.
Now, when you provide negative feedback, do you want to make it quick and painful or slow and less memorable?
My guess is that you want to make it stick. So do it quickly with large impact, it is more hurtful, but more clear and it sticks better.