I believe the answer is that Zhu Bajie becomes better version of himself and is given
reward of being the “Cleanser of the Altars”.
In “Journey to the West”, Chinese novel written during the
Ming dynasty (16th century), attributed to Wu Cheng'en, Zhu Bajie
(Pig) doesn’t achieve enlightenment as his fellow pilgrims. Although, Zhu
becomes much improved version of himself, he is still too much a creature of
his base desires. As a reward for his pilgrimage's success, he is rewarded with
a job as "Cleanser of the Altars" and all the leftovers he can eat.
