For thousands of years, horses have survived on this planet. Without that flight to fear behavior, horses would have diminished long ago. However, it is these instinctive survival skills they use daily that keep humans and horses from becoming partners.
Humans disregard thousands of years of natural, bred-in, survival instincts.
When humans interact with horses, they need to portray a safe, comfortable attitude toward them. Instead, humans usually confuse the horse and project fear throughout their training methods. Another aspect is that humans are very passive, begging for acceptance. The manner in which people act toward horses reassures the fact that humans are natural predators. Practical Horsemanship' is more than just proper technique.