-Uggs [acid burst] me off to no end. They make people's legs look fat. They're not so bad with pants, but with a skirt? Not even a model could make that look good.
-Boxers hanging out of pants that sit nowhere near the waist or hips. For the last [tornado fang]ing time, pull those up. You can have them at the hips and show a little waistband and that's fine, but if your ass is hanging out, ugh. I don't want to see your ugly boxers. If a guy's got a nice butt and he's wearing flattering underwear, I don't have a problem with it. But boxered asses hanging out are just plain NO. (I'm not saying this with any particular demographic in mind, it just does not look good on anyone. Some places will even write you up for indecent exposure if you show too much underwear.)
-Anyone wearing elastic-waistband "denim" will be unceremoniously defenestrated. (This is mainly just a problem with older women.) If you want something comfortable and easy to wear, sweatpants are fine.
-Anyone who isn't a teacher and wears seasonal sweaters, most of the time, won't look good in them. There are exceptions.