I've counseled corporate clients many times on removing senior-level executives, and the odd Paterno termination process, with its hand-delivered letter and curt telephone call 10 minutes before the Board of Directors announced the firing, makes perfect sense to me.
It's clear that there has been an acknowledgment at the senior levels of Penn State leadership that Paterno needed to go for some time. Several years ago, representatives of the University management team went to Paterno's house to ask him to step down from his head coach position. Paterno threw them out. Either before or after that particular event, the realization must have come to the Penn State board that by wallowing in the financial success of the football program, and allowing Paterno's successful record in football (unblemished by NCAA violations) to become the focus of the University, they had created a monster that perceived itself to be totally outside their control.
Now, it's great to be a monster, as long as you're only facing people with figurative pitchforks and torches. But as a monster, you have to be careful not to do something so, well, monstrous, that ultimately allows the pitchfork crowd to get a monster of its own.
That's what Paterno ended up doing here. And because he's a monster, or because he's 80+ years old, or for some other reason, Paterno didn't realize that the monster he created was about to gobble him up. By acting like a monster himself, Paterno set up a situation in which the university owed him literally nothing in terms of process, hearing, or explanation.
In short, Paterno become dangerous to the brand he mistakenly thought was his. The economic value of continuing with him to the end of the season, or even giving him the opportunity to defend himself (I'm not sure he can, anyway), was less than the economic damage his presence directing the team would inflict. The monster of terrible, continuing publicity, was bigger than the monster of Joe Paterno.
An easy choice, in the end.