That's because, in MY opinion, a lot of horse behaviour also comes down to people's attitudes, and 'you get what you expect' tends to be one big (general
) truth of the matter!
Self fulfilling prophesies abound!
Also, there is horse behavior, based on what they evolved to be, that is universal
Factors like individual personality, up bringing, all apply, like in any living breathing entity, but a horse is still a horse
What modifies their behavior, learning curves, inheritance of things like 'cow sense', braveness, can be entirely broad topics on their own
When not recognizing a horse for what he is, treating him like a dog or an other pet, is when humans get into trouble
There has also been actual research done, by a neurobiologist, which shows that horses growing up, free to explore , versus those mainly raised in confinement, have an actual greater learning capacity, due to brain development
The pertinent facts , brought up by a vet that specializes in horse behavior, points out that horses do best, both mentality and physically, when they are allowed to live like horses, much as possible
That means the ability to move almost constantly, herd living conditions
At times, for our own good, we have to have horses able to accept some limitations, far as those conditions, and he states that horses have a great ability to adapt, but we must be sure to never exceed that ability!
Many horse illnesses, stereotypic behavior, lameness, are directly due to exceeding that ability to adapt