His final season was dire. Every attack was telegraphed, usually ending up with Navas or Kolarov twatting the ball low into the first defenders legs. We won games because we had good players, not because the were particularity well coached
I have not gone into games more or less knowing we would not win, yet in his last season there was at least 3. They were Leicester and Spurs at home. He had/has no flexibility whatsoever and we walked into counter attacks that the opposition set
I would go as far as saying that West Ham are likely to get relegated with him as manager such was his lazy attitude to coaching, tactics and developing players. Set-pieces were another area, we didn't look like we had ever set up on how to defend them and had very little idea on how to make the most of them in attack
On top of that, he appears to value a hierarchy in the squad. Bony played no matter what in-front of Ianacheo, for example. He also runs players into the ground.