There is no "perfect" size 7

I've heard it said time and time again "I don't understand why these shoes don't fit, I'm a perfect size 7" or " I just can't wear his shoes, they never fit". I'd like to tell you why this just isn't true. Each shoe and fit are different even within the same designer, it all despends on the shoe last. What is a Shoe Last ?
The solid form around which a shoe is molded.

I try to tell people that there is no such thing as a perfect size. Every designer uses their own unique"shoe last". Each "shoe last " is designed for a particular heel height, toe shape, and type of footwear. Different designers have different shoe lasts for each heel height or look (thus different fits) which means multiple shoe lasts for their designs. So, even though you may have one designer who makes a lot of different styles, they may have used several different shoe lasts and each will fit differently. Just because one shoe in a collection doesn't fit, it doesn't mean others in the collection may not. The fit of a shoe depends on the design, shape and volume of the Shoe Last.

The shoe last must represent the anatomical information of the foot, at the same time giving the finished shoe a pleasing and fashionable appearance. Take a look at the one below.

Traditionally, shoe lasts were made of hardwoods, such as Maple or Beech.
Modern day shoe lasts are made of high density plastics, that are 100% recyclable. So, don't think that every shoe fits the same because if they did they would all look the same.