I don't exactly agree with this mindset, while in some cases it is true, it's not always the case. My most friendly roosters were also my least aggressive ones. In addition, take for example a breed like the aseel, they are known for being very human friendly, and a good aseel should not seek to attack its owner. Now, I agree that there is a difference between friendliness and a rooster testing the boundaries, something that can get misunderstood by the beginner keeper. And finally, temperament among other things is breed dependent, so some breeds that are known for being friendly are going to have roosters that are truly that