Teams: Australia & Newcastle United
The majority of players who retire, like Couts said, are physically and/or mentally not up to it anymore or they're just sick of it.
Then you have guys like Matty Knights, Mick Martyn, Adrian Fletcher, Chris Bond, etc who rightly or wrongly feel they have another season or two left in their body but they get pushed out for cap reasons or the club wants to blood youngsters/start with a clean slate.
Remember 1991? AFL lists were 52 players ... now that's shrunk to a tiny 38 plus Rookies/Vets. That means that in the space of a decade that's 14 players per club there's no more room for.
"They picked on the wrong man - and the wrong country. It was like pouring petrol onto a fire as far as I was concerned.
There's an old saying that the dog that barks loudest never bites. They did a lot of barking but we bit them pretty hard. Uruguay's attitude just showed how scared they were of us - it was their last resort."
- Vincenzo Grella, Parma & Australia.