When I turned 65, my contract to teach at the GSB was no longer renewed. No more teaching assignments. No use arguing that when one gets older, ones faculty becomes dimmer.
In the other classes where there were senior teaching staff, there was much criticism on: the appearance, (probably even the smell - amoy lupa), the teaching methods, and old edition of their references.
Although there were inconsistencies (some senior colleagues stayed on) by and large most of the elderly were asked to stay at home once they were 65: presidents, department heads, etc.
Such is the way so that only fresh more vigorous individuals carry the torch. With more energy zeal and enthusiasm to carry the task.
A study was made regarding having the elderly run the community vs those run by young blood. The latter scored well on many fronts.
Well anyway, we did our best when we were younger