While I will admit Haley had a lot of factors going against him that could make most coaches lose (talent, injuries, cheap ass owner), he has done plenty to give him the ax. The blowout losses (Buf, Mia especially) showed just how unprepared the team was going into each game. That's his fault. His pre-season plan was a disaster and showed in that first game. His constant conflicts with coworkers is a sign he didn't belong. The regression of Cassel this entire season is his fault, even if it was him who improved him last year.
Chiefs have a lot of problems bigger than Haley ever was. Not an excuse for being a terrible head coach though.