But not always...
I landed at Singapore in a BA 744 and on shutdown the FO came on the PA and announced that the captain had just that minute told him that it was his (the captain's) final flight as he was retiring and would be returning to London as pax. Perhaps we'd like to congratulate him. Which we did.
I supose there's an argument that that's the professional, albeit boring, way to do it. A bit like the RAF not allowing studes to make their final sortie on a course solo.