Why do salons put you under a HOT dryer for some color. but not for all of them ?????

Because vibrant color requires heat to bond to your hair.Why do salons put you under a HOT dryer for some color. but not for all of them ?????
Because it depends on the type of color used by the salon. They all don't need the same thing to make the chemical process happen.Why do salons put you under a HOT dryer for some color. but not for all of them ?????
ask them u idiot
it depends, if the color contains bleach or not. Also- some salons, use lights instead of dryers...