What behavior does a quarter horse have?

Although no two horses are the same, and their personalities can vary widely, Quarter Horses tend to be reserved and laid back. They are good for cow ponies, but are often low on the list in comparison to other breeds concerning their interaction with their riders and their willingness to work. The Quarter Horses I've known have been defensive, and difficult to work with, although a few have been mildly even-tempered and good mounts.