I disagree. Making the playoffs is not the only measure of success, and its contingent on many things going right.
but your position still seems to ignore the talent assembled. Did the GM get the necessary talent to compete? That's not on the manager, nor can the manager make the Johnny Giavotellas of the league suddenly turn into Ryne Sandburg.
There's also the issue of injuries. The starting pitching for this team in the last 8 years has had about a gazillion TJ surgeries. That's not something the manager or anyone else could have controlled. It make be simplistic to say so, but I doubt any team could have survived the devastation our starters have gone through. Not even Maddon or Francona, the managing messiahs of aw.com, could have made this team more successful while dealing with those kinds of huge setbacks.
I'm glad we've had Sosh for the best run in team history and that we were all here to see it. I honestly don't care if he stays or goes next year. Maybe it's time for a new leader, but not a single one of us here can adequately measure his value to the team. Some of you are going to be sorely disappointed when you find that the next manager is another Dave Garcia type.