Every year, there are coaches on the hot seat, and every year, a few of them lose their jobs. Once in a while, a coach will lose their job mid-season, and those situations never turn out well for the team. Last season, Wade Phillips lost his job following a couple of blow-out losses, and the team seemingly rebounded once Jason Garrett took the reigns. What happened? Did the Cowboys suddenly get exponentially better than they had been prior to the change? No. It was the effect of the "lame duck" coach.
The term "lame duck" coach implies that everyone knows that coach will be losing his job at the end of the season. Lame duck coaches have no incentive to push their team once it's apparent they won't be keeping their jobs, and that's how I would determine whether or not to fire a head coach during the season. Owners just need to ask themselves, "Is [insert coach's name] a lame duck? If the answer is yes, make the move now. Maybe the team can try out an in-house guy. If that works, great. If it doesn't, it's no big deal.
If the answer to the above question is no, then don't fire the coach. It's that simple. If that status changes at some point later in the season, then it's worth making the move. The one thing I would hesitate about would be making the move very late in the season. That wouldn't give the interim coach a fair shot at proving himself.
Now, let's move on to a few head coaches that are currently feeling the heat. First, let's analyze Tony Sparano, head coach of the Miami Dolphins. Is he a lame duck? Yes. Everyone knows that it would take a complete 180 for this team to hang onto Sparano, and they just don't play in the right division for that. The Bills, Patriots, and Jets are all far better than the Dolphins, and that accounts for 6 games a year. They should go ahead and try an interim coach. the season is still young, and maybe they can salvage something respectable from the season if they make the move.
Next up is Jack Del Rio of the Jacksonville Jaguars. Is he a lame duck? No, not yet anyway. Del Rio has to navigate a rough schedule, having a rookie quarterback, and a fan-base that is showing him no support. All that against him, the Jaguars are still only 1 game out of first place in the AFCS, and the rest of the division also plays a very tough schedule. The Jaguars' defense is far better than last year, and if they could pull off a few upsets, they could still play meaningful games in late December. He may get to be a lame duck coach later in the season, but he's not quite there yet.
Todd Haley of the Kansas City Chiefs is a another coach that is on the hot see. He, as well as Steve Spagnuolo of the Rams, is not a lame duck yet. Both of those guys have had their teams under-perform for the first 3 weeks of the season, but there's still time to turn things around. The Rams play in football's worst division, and the Chiefs played the Chargers very, very close in a heartbreaking loss in week 3.
With the exception of Sparano, these coaches haven't lived up to expectations, but they shouldn't be considered "lame duck" quite yet. They deserve to be given time to turn things around. We're only going into week 4 after all. The season's still young, and stranger things have happened than a few coaches getting their teams on the right track.