Because he makes terrible decisions...
Why does he continue to throw Balfour out there every single game? Keep in mind before you claim Balfour's talents, that he wasn't talented enough to make the team at the start of the year (just like last year's Silver Slugger Carlos Pena). Game five, why does Balfour face Ortiz after a double and two singles. Balfour throws the fastball. When they catch up to it, it's time to bring in someone else.
Game 5, ball goes over BJ's head, but why was BJ playing shallow center?
We're a young team. His primary objective has got to be keeping them focused. So, after his two HR night in the ALDS, where is Evan Longoria? He was living the rockstar dream all night at the USF game with the college girls. Hey, that's what we all want, but there is a time to party and a time to take it seriously. The reason Kazmir struggles from time to time is because he gets caught up in the rock star life himself. Let's just go out on a limb and say that perhaps certain illegal drugs and baseball don't mix.
Navi, perhaps the slowest man in all the world, and you send him to second? Bartlett isn't a power guy (HR was lucky), but that's not a very high percentage call, especially with Navi's bad knees.
How much does Gabe Gross have to struggle to get taken out?
He's done some good things too, but there is a lot that goes on off the field that he doesn't monitor at all that definitely affects us on the field. The winning we're seeing this year has very little to do with him. It wasn't HIS decision to sign Wheeler or Balfour or any of the other bullpen players we signed this year.