Because of who they were and how the subject was broached. They may have said that Goss did a good job, but now he was becoming a lightning rod and an obstacle to change given the McCarthy firing. In order to get the CIA reform back on track, it was necessary to put someone else in charge.
Something there. Perhaps it's like a limit for hunting season. Each CIA Drector can only put a certain number of trophy heads on the wall until he has to let the next guy have a turn.
Ok, interesting. Thanks for expanding on it.