Why God Erased His Own Temple

What would move the Creator to tear down His own Temple? The Torah, Prophets, and The Jewish Sages' commentaries in the Talmud (TB Yoma 9b8) engage with this question head-on, in order that we, their successors, might not fall into the same patterns that led God to act as He did on the 9th of Av --- in regard to both the 1st and 2nd Temples, which feel on the same calendar date.