“Josh will leave the Club with our best wishes as he endeavours to explore senior level opportunities with Adelaide,” Hamilton said.
So as I thought. He's the same age as Paddy Ryder and Tom Bellchambers so it's unsurprising he sought other opportunities. He was a rookie, reliant on injuries to get upgraded and get a game, and had two entrenched ruckmen aged 22 and 23 at the time who were senior-listed and ahead of him in the pecking order.
Draper's situation is a little different, if he left it wouldn't be for lack of opportunities.
It is different but trade value wise I don't think it matters. Uncontracted and no games, leaving for a better contract or better opportunity, does it really matter?