Do you really believe that every team who fails to win the Super Bowl is as much a loser as the rest? I've never understood that sort of mentality. By that logic, the Eagles 2013 season was as much of a failure as the Eagles 4-12 2012 season or 8-8 2011 season? The 2008 Cardinals, who lost a close Super Bowl to the Steelers, were as much a loser as the 0-16 Lions? Come on.
In some ways, I agree with the concept that any season you don't win a Super Bowl is basically a failure.
In an ideal world, I'd like to have the #1 pick in any season where the Packers didn't win the Super Bowl. The only problem with that is that if you're the worst team in the league, you probably have a number of operating and coaching difficulties that can be just as hard to truly cure as a lack of talent. So it's not reasonable to go from the #1 pick to a Super Bowl win and back again.
So with that in mind, I give some credit to the notion that every NFL team is persistently in a state of either peaking or regressing and it's about "getting over the top". In that scenario, a season is only a success if you're on the left side of that bell curve and moving on up. If you never actually win the Super Bowl however, retroactively all those "great seasons" in some ways just become missed opportunities and a failure. The Andy Reid era in Philly is just one huge missed opportunity which is basically a failure.
The 2011 15-1 Packers were a massive failure. Most every season for the Patriots is a failure because they consistently win 11-14 games a season without anything to show for it. It all depends on where a team is headed really.