every other halo game, besides reach, had ranks too. this playlist is being made for competitive play. A skilled playlist that competitive players would like to get their 50 in. Who would want to join a game in progress and loose and there would be nothing you can do to about it and loose truskill rank.
if you dont like it, dont play it. Keep playing your no flow, unbalanced, random instant respawning, getting rockets for free, people running around with boltshots playlist known as infinity slayer.