This, I think, is where the problem may lie.
I am guessing that Miles HAS BEEN a distraction for the Grizzlies.
The transparent attempt to play games with other teams, to tweak a "rock star" GM, to thumb your nose at a rich and obnoxious owner, has nothing to do with what the young players on that squad are trying to do and build.
Imagine you are Gay, Mayo, Gasol, Conley, etc. You are trying to build a team, get better, learn how to play a team game, all while being competitive and stealing a few games here and there. And this is what happens early in the season.
Along comes this Miles thing, and as a player you can't fathom what the heck this dude is brought it for. And you get miffed when the reporters mostly want to interview him, and when they do talk to you it is to ask questions about Miles. Then it starts to dawn on you that the ownership and management are clueless and not committed to builiding a competitive program.
Kinda sucks the life out of the effort. Being confronted with the reality of the situation. Collapse follows.