Polo necks - I am too short and always wondered why they were horrible on me, now I just don't wear them!
High heels - and I used to wear them every day. I have some amazing designer ones but I cannot even wear those, the pain from my feet shows in my face - not a good look!!
Pleated skirts - DSis looks amazing in these but I look frumpy.
Anything tucked in - I am inverted triangle and really need to skim my tummy area.
Skinny jeans - just realised in the past year, they look all wrong on me. I have very slim legs but my legs look dumpy in them. I still have a couple of pairs for wearing with wellies on those awful wet days but when I eventually find a better alternative, they too will head to the charity shop. I look so much better in straight leg or wider leg, cut off at the ankle to show off my tiny ankles. But skinny jeans make my legs look fat (how I don't know) and they are really uncomfortable to wear after 3 c-sections.
Parkas - I have never found one that makes me look good (I have only ever seen really, really expensive ones looking good on very slim, very tall women who are wearing very expensive shoes, jeans/leggings and jewellery). Otherwise I think they make women (and men) look like homeless people.