If, like me, you don't often wear a dress, then it's hard to know what suits and what will fit and look nice. So all you do is go into a shop, pick something off the rail that looks pretty and is about the right size and then you try it on.
And that's when you realise that dresses are made for teeny, tiny little women. Not women with long limbs. Not women without a waist. Not women with a bosom. Not women with hips. Not women like me.