There are some mistakes - some errors in judgment - that should not undo a lifetime of good. Others are so egregious that reasonable people simply are unable to look at the offenders the same way ever again.
This is where we are with Joe Paterno, who was fired by Penn State's board of trustees late Wednesday night.
It was the right decision.
It is sad and regrettable, but in these extreme cases, the biggest regrets should always be in the hearts and minds of those who knew better, but failed the biggest tests of their lives.
The test that has come to define Paterno - and cast a huge shadow that will largely obscure every good thing he ever did - didn't come in 46 seasons as the Nittany Lions football coach. It came on a random Saturday morning in 2002, when then-graduate assistant Mike McQueary and his father, John, arrived at Paterno's house with a story to tell.
Mike McQueary allegedly stumbled upon former Penn State defensive coordinator Jerry Sandusky abusing a young boy in the shower room in a campus building. McQueary was shocked and repulsed, but did nothing to stop what he saw. Instead, he called his father, who suggested the two go to Paterno.
Paterno then passed a version of what the McQuearys told him to Penn State athletic director Tim Curley and Gary Schultz, a university vice-president.
The story apparently died with them. No one - Mike McQueary, his father, Paterno, Curley or Schultz - ever notified the police.
How do human beings obtain this kind of knowledge and make the conscious choice to do nothing? How do they make the decision to prioritize Penn State and the reputation of its football program over the physical safety and emotional wellbeing of innocent children?
How have these men slept at night for nearly a decade with what they knew?
They had the power to confront evil in their midst and stop it, but they did nothing.
They turned their backs on children.
They kept Sandusky's vile secret.
They knew.
They did nothing.
They should be ashamed.
They should be unemployed.
They should be in jail.
Curley and Schultz have, in fact, been charged with perjury for lying to the grand jury about what they knew. Curley has taken a leave of absence and Schultz has stepped down.
Paterno, 84, and Penn State president Graham Spanier followed late Wednesday.
Incredibly, there are those who still defend Paterno and maintain he did all that was required of him when he took the story Mike McQueary told him to Curley and Schultz.
These people are delusional. Paterno - arguably the most powerful man in Happy Valley - had an opportunity to act on behalf of Sandusky's victims. He had a chance to do something far more noble and important than winning a football game.
He failed.
With that failure out in the open now, Paterno says he wishes he had "done more" and that he is "devastated by the developments" in the case.
Too little, too late.
Last week, Paterno was a national treasure. His fall from grace is a stunning epitaph to a career that was viewed through an entirely different prism just a few days ago.
You want to feel sorry for Paterno. For decades, we viewed him as an example of what was good about college football. Now, he's old and everything he has worked for and all he has accomplished have been forever tarnished.
But, if you're a human being, that's when you think of the children. It's time someone finally did that.
That's when you realize that the people who had the power to stop this years ago are getting what they deserve.