The average body size is generally about 90 kg to 150 kg. Uniform size clothes are very inclusive of figure, and people with different heights and weights will have different style characteristics, so 140 kg bridesmaid clothes can be worn in uniform size.
In order to let more people wear uniform clothes, they tend to design slightly narrow shoulders and loose hems. This style can make people look tall, and the special treatment of waist and shoulders can make most people wear it.