Hair should never:
Be mistaken for a hat.
Resemble a craft, such as macrame.
Render a thorough washing impractical for a period of longer than two days.
Contain color(s) not present in the simple prism of white light.
Require the presence of more petroleum based products than your car.
Provide shelter for critters normally targeted by the Orkin Man.
Cause threat and contraband sensitive canines to go on alert.
Look like a lacquered pineapple.
(This list is by no means offered as complete, but it can serve as a fundamental framework for the "Dont!" points of hair design.)