Some are released from their contract (Carlito, MVP) and some were forced to retire by a match (HBK, Ric Flair, Lita) and some were forced to retire due to injury (Edge, Chris Jericho) Others just decide to quit (Batista)
Chris Irvine is Chris Jericho, and Adam Copeland is Edge :) "no Jericho is called chris irvine, and edge is called something copeland" No edge is wayyyyy better looking then Jericho --- Edge? not really. his body and his hair are nice... but his face ... well, not the best.
No. Judging from No Mercy, he faced Chris Jericho for the World Heavyweight Championship. Now, why would he want to retire once he has won this title. Unfortunately, he lost. Lance Cade interupted, since Chris couldn't beat Shawn by himself. That just shows.