I've been playing comp for a whole year and I finally achieved Immortal just two weeks ago. Though quite recently, I queued up with a cypher who just started trashtalking our teammates when one guy died on literally pistol round. Dude still barking when we just died a round still. I lost the match 4-12.
Riot should add a avoid a teammate system as I literally queue up with him "again" during the second match.