Yea, but they do it in a way where the longest reigning champs are favored, and then #2 or even #3 guys who have been up top for a while can be in it. They use a seniority system.
Someone like MM could easily be #1 without the seniority system. Not only has he beaten the top guys in his own division, but he had excellent wins and was a contender against bigger guys one division up.
Actually, nobody comes close to that!
"C'mon Andy, let's go! Go for the single leg!" - BJ Penn
"C'mon everybody, Let's hear it for Josh KosCHECK" - GSP
"Lyoto won all 5 rounds." - Anderson Silva