Why Don't Supermodels Brush Their Hair?

I keep seeing pictures of models roaming the streets or attending events with disheveled hair. I can't understand why they don't take the time to brush it when beauty is their trade. I can understand why they go messy after getting primped day after day, and I don't expect anyone to look perfect all of the time. But some models consistently look sloppy. Why do you think this is?

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