The Magpies were bundled out in the first week of the finals after a shock elimination final loss to Port Adelaide at the MCG.
The anger arising from such a disappointing season was evident in the key pair's addresses at the club's Copeland Trophy count at Crown on Friday night.
"It's sad to see since 2010 that a pervasiveness of selfishness has crept in to our club," McGuire said.
"We won in 2010 by being side by side. Side by side means being that always.
"It's not about being side by side when you're being supported and then turning your back when it doesn't suit.
"Any form of selfishness will not be tolerated."
Buckley said the club had already begun planning for 2014, while also reviewing what went wrong in the season gone by.
He arrived at the blunt conclusion that the Magpies had been their own worst enemies.
"We've got the necessary talent to contend, but this year we beat ourselves," Buckley said.
"It won't happen again and we're putting everything in place to make sure it doesn't."
Buckley said the club would come first next season.
"The brutal reality is that the club will always be bigger than the individual," he said.
"Side by side is more than just a line in our club song. It's an expectation. It's demanded.
"The club comes before the man. Not the man before the club."
On a night when 2010 premiership stars Dale Thomas and Heath Shaw declined the club's invitation to attend the best and fairest, Brownlow medallist Dane Swan vowed he would never quit the club.
Thomas and Shaw are expected to find new homes as early as next week, while Swan's long-time friend and teammate Alan Didak is also searching for a new club after being delisted earlier this month.
"It's a pity Heater and 'Dids' couldn't continue their careers here but I still love them as should all of you. They're premiership players," Swan told the audience.
"(But) I love the footy club. I certainly don't plan on playing for anyone else. I’ll be a Pie for life.
"You won’t see me walking out of this club."