There's speculation (conspiracy theory maybe) that the reason Duren has an infinitely long leash is that his contract has already been worked out. They already had talks and committed to maxing him, so they have to force this and treat him like a max player.
Contrast that with Ausar who can sneeze wrong in one game and get benched no matter how many times he saves this team while Duren can play 11 bad games in a row and not lose his playing time.