Placements are flawed
It is absolutely ridiculous to have plats and diamonds on the team paired up with silvers who got lucky in their placements. They get absolutely stomped in 99% of my games and we unlucky plats/diamonds who did terribly in placements have to suffer through the feeding frenzy of silvers on our team.
Why on earth would it be okay to have silvers and diamonds on the same team?
This climb up the ranking ladder is based off of luck and which team gets the lucky silvers.