If Ponder one day became Archchancellor

[KamexKoopa]

How long do you think he'd last? Ridcully once said Ponder (and his ilk) would look at him as if he'd started to dribble if he asked him to perform a leviatation spell, so how would he cope with combatatant spells? Dead Man's Pointy Boots seems to have quietened down under Ridcully, but an enterprising wizard who saw an easy target would probably go for gold

[Tonyblack]

I'm not sure Ponder would want to be Archchancellor even if he could. It's pretty clear that he already runs the place and the university would grind to a halt without him - and he knows that. I think that's enough for him. All the power without the responsibility.

But the university is a very different place than it was in the early books. It changed pretty much when Ridcully turned up. Which incidentally was around the same time that Ponder turned up as well.

[Molokov]

And also about the time that the Bursar stopped being the calm, sane man who ran the University (see Moving Pictures, Reaper Man) and kept going more and more insane, and thus dependent on Dried Frog Pills. Ponder has basically taken over every administrative role the Bursar used to do, except perhaps the actual bursary/finances.