a legitimate request by bucking.
 Rodeo broncs and bucking bulls are used specifically as bucking stock, usually bred to be prone to bucking and encouraged to buck whenever a rider is on their back with the help of a "bucking strap" around their flank. 
 Fear of loud and noisy machines, like cars, trucks, trains, and planes. In response to tragic injuries that have resulted, the American courts have uniformly held that "the needs of a modern, industrial society often conflict with and generally must prevail over the delicate sensibilities of horses."

Ordinary riders need to learn to ride out and correct a simple buck or two, because it is a relatively common form of disobedience.  Further, at times, movement akin to bucking is actually required of ano longer have to work), then the horse must be re-schooled by a professional trainer.

It is important to address the problem of the bucking immediately. Even with good cause, it is a potentially dangerous disobedience that cannot be encouraged or allowed to continue. However, a rider does need to be sure that it is not triggered by pain or poor riding. The horse's turn-out schedule should also be assessed, as extra turn-out will give a horse to release extra energy before a rider gets on. In certain cases (such as a show, when horses are unable to be turned-out for extended periods), longeing the horses for a brief period can help calm excess energy, allowing the rider to mount, and ride safely.

If poor riding is the cause, special