One mistake, I think, is not treating a rooster with the respect he deserves. Unless he is a truly vicious rooster, most are aggressive because they are protecting their girls. I’ve found that a simple spray bottle with water in it does the trick. A couple of squirts and the roo figures it out. My roo recognizes the spray bottle and respects me when I have it with me – which is any time I go into the chicken yard. A friend of mine picks his roo up and carries the roo around as he does light chores, establishing dominance over the roo. I think the biggest mistake made with a roo is abuse which, like I said, unless the bird is truly vicious, is uncalled for and cruel.