I'm not ready to give him the axe but these are points that worry me:
We've seen no improvement all season long (other than Corey Brewer - credit to Rambis, Kevin Love at times), his rotations are questionable (i know it's all about developing our players right now but his rotation is still bad), we play a system that does not benefit the strength's of our players, Jonny Flynn wasn't allowed to play pick & roll all season long although it's one of his huge strengths, players who clearly don't give a **** about the team and whether we're winning or not play to much minutes (it's you Sasha!!!

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It looks like Corey Brewer has become the teams go-to-scorer, Rambis wanted Kevin Love to guard Carmelo Anthony, Al Jefferson gets (way) to few shots at times even if he's hitting them at a high percentage, we don't know the word defense (Nobody has improved on that end of the court over the season. You might even say they have become worse).
Overall, we all knew it was going to be a tough season but nobody would've imagined that the team could play this bad at times. What is most questionable is the effort of the team. How can you lose 152- 114 when you're paid milliones of dollars? There is just no excuse.