Why do we think one size will fit all and why do we approach this with horses?
Well I think it comes down to some basics:
Time – we are all time poor wanting more hours in the day
Value/Cost – it is easier to buy the same that can be used for all horses and it leads up to time cause you don’t have to think what you are doing
Unknown – you don’t know what you don’t know.
HOWEVER not one size fits all in human life why would you expect it to be different in horse life.
I will use my horses as an examples, firstly they come in different sizes, I have a Clydesdale Cross vs Thoroughbreds so different bone structure, height, weight, hoof thickness and size, fur, length of mane and tail, even different predominant muscles as one is a sprinter and one is built for pull.
So my thoroughbred reacts to change in climate quickly and will lose weight, so she is rugged and fed a hard feed regularly to keep it maintained. She has high withers so her saddle needs to accommodate that as well her halter size is between a cob and full, she has thin walled hoofs that can crack.
My Clydie X, cannot wear a rug because she sweats so much even in the coldest of weather, she is a do gooder and would get fat if I fed her hard feed, her head is large and strong so she needs warmblood size, she needs to be protected from the sun on her muzzle as she has pink skin, her back is wide and she is short in the back so we have to be careful what saddle we use and her hoofs are the size of dinner plates and strong.
This of course are obvious differences but even with another of my tB it is the same, he is a medium do gooder as far as food, has a long back and a normal wither, has extremely tough hooves and a larger head.
Imagine you have a size 8 foot and I gave you my size 10 or the other way around. So when friends tell you what works for them, listen, valuate and know your horse.
So in short we need to adapt ourselves and routine to what our horses need and if we love them it won't be hard.