There are about 12 rotation worthy players on this team, yet ideally a rotation should only be 9, maybe 10 players deep. Somebody is going to be left out at times, and there will be guys who get less playing time than they might deserve.
Lee is a decent player, but he doesn't bring much to the table other than scoring, and he's not good enough at that to be a go-to guy on the second unit or anything.
He has no future with this team and he likely knows it, so he's anxious to get out there on the floor and audition for somebody to pick him up and give him starter minutes.