conjunction
precisely because of that; that's exactly why
Used to state that a preceding reason or fact naturally leads to a particular result or expectation. Often implies 'all the more so' or 'for that very reason'.
彼は努力家だ。それだけに、失敗したときの落ち込みも大きい。
He is a hard worker. Precisely because of that, his disappointment is all the greater when he fails.
This restaurant is popular. That's exactly why it's hard to get a reservation.