If Jaylen Brown moves clearly ahead of Green on the depth chart, Marcus Smart improves, and maybe RJ Hunter looks like a rotation-worthy player, does Gerald Green become expendable? Or maybe he just doesn't work out and can't quite grasp the defensive scheme. Is he someone who might end up being flipped for another player who might provide depth that could be more needed at a different position or dumped for a second-round pick to clear a roster spot for another player?
Some people are excited about Green's addition, but he's not guaranteed to be a useful player. He signed a one-year deal, so he's not in the long-term plans. It's almost like he was signed so that Jaylen Brown didn't have to be force-fed Evan Turner's minutes and can be brought along slowly if needed.
On the other hand, he may be useful enough that he is wanted on the roster as part of a deep playoff run, with the intention of letting him walk after the season without getting anything in return, leaving a spot open for the next reclamation project.