Besides your horse’s health, the 3 fundamental pillars to having a horse successfully barefoot are: Food – Environment – Stimulation
WHAT’S HORSES’ FAVOURITE ENVIRONMENT?
Facts are very well-known by now: horses prefer to live in a stable herd, outdoors, moving along constantly to nibble on anything and everything. Besides all the benefits this environment provides for the horse’s mental health, let’s focus more closely on the feet aspect.

HOW DOES IT HELP WHEN HORSES HAVE FREE MOVEMENT?
By living outside, the horse will travel much more distance than if he / she lives in a box (even she / he has access to an automatic walker). She / he will also have the choice (most of the time) where to put her / his feet – preferably not in pee and poo. The terrain might even be up and / or downhill!
HOW DOES IT AFFECT THE HOOVES?
Movement promotes hoof stimulation, hence, internal and external structures development. The more the horse has to use her/ his feet, the more stimulated all the different structures will be. It means that if some of the structures are underdeveloped, they will grow healthier through movement, as they will be encouraged to do their job.
Of course, do not expect a weak frog to be 100% operational within minutes. It takes time to build everything up. Free movement is preferable to develop the feet. You might not want to force too much movement on your horse if her / his feet are not yet ready to deal with too big of a hack or too long a lesson.
If the horse already has healthy feet, then great! Movement will keep them nice and happy!
HOW CAN YOU HELP?
To be honest, a stabled horse is not the best barefoot candidate. Less movement in most cases, and dejections are detrimental to the external structures, and so, might impact the internal structures, even lead to problems higher up the horse.
I know most of you are careful to board your horse where hygiene is up to standards, but it is unfortunately highly impossible for your horse not to stand in dejections while in a box.
It is also true for horses in pasture that just stand in muck & mud around the hay bale. But they get away with it more easily because of movement (and feet packed with mud, kind of protecting their feet from poo and urine sometimes).
Perfect is the enemy of Good: Do your best!
Do not despair, though. Many horse guardians are successful in keeping their horse barefoot and stabled. It is, however, much more work and commitment for them (more hoof treatment & protection, more time working the horse or just taking him / her out of the box for long period of time, etc.).
Here is another article giving tips on how to set up a funnier / healthier home for your horse!