As it says in the Infinite Life Sutra below, Amida vowed that those reborn into the Pure Land would have “one more life” before attaining Buddhahood.
It’s not a place, according to traditional Pure Land teaching, where one instantly attains Buddhahood:
If, when I attain Buddhahood, bodhisattvas in the Buddha-lands of other quarters who visit my land should not ultimately and unfailingly reach the Stage of Becoming a Buddha after One More Life, may I not attain perfect Enlightenment…
The Buddha said to Ananda, “All the bodhisattvas in the land of Amitayus will ultimately attain the Stage of Becoming a Buddha After One More Life.”
Acording to Master Sheng-Yen, the Pure Land is a training ground for Bodhisattvas, who must then return to this world to attain Buddhahood. He says that only in the human realm can one fully attain Buddhahood:
Nam-mô A-di-đà Phật